<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <title>Expanding (3x + 4)²</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: transparent;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
    }

    .main-wrap {
      width: 100%;
      max-width: 560px;
      display: flex;
      flex-direction: column;
      gap: 12px;
      align-items: center;
    }

    /* Expression Header */
    .problem-header {
      font-size: 24px;
      font-weight: 700;
      text-align: center;
      color: #1e2945;
      letter-spacing: -0.5px;
    }
    .problem-header .t1 { color: #2563eb; }
    .problem-header .t2 { color: #059669; }
    .problem-header .t3 { color: #7c3aed; }

    /* Cards Row */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 8px;
      width: 100%;
    }
    @media (max-width: 440px) {
      .cards-grid {
        grid-template-columns: 1fr;
      }
    }

    .step-card {
      background: #ffffff;
      border: 2px solid #e2e8f0;
      border-radius: 10px;
      padding: 10px 8px;
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      cursor: pointer;
      user-select: none;
      transition: border-color 0.25s ease, box-shadow 0.25s ease, opacity 0.25s ease;
      opacity: 0.45;
    }
    .step-card.active {
      opacity: 1;
    }

    .card-blue { border-color: rgba(59, 130, 246, 0.3); }
    .card-blue.active {
      border-color: #3b82f6;
      box-shadow: 0 4px 12px rgba(59, 130, 246, 0.18);
      background: #eff6ff;
    }

    .card-green { border-color: rgba(16, 185, 129, 0.3); }
    .card-green.active {
      border-color: #10b981;
      box-shadow: 0 4px 12px rgba(16, 185, 129, 0.18);
      background: #ecfdf5;
    }

    .card-purple { border-color: rgba(139, 92, 246, 0.3); }
    .card-purple.active {
      border-color: #8b5cf6;
      box-shadow: 0 4px 12px rgba(139, 92, 246, 0.18);
      background: #f5f3ff;
    }

    .card-label {
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      margin-bottom: 4px;
    }
    .card-blue .card-label { color: #2563eb; }
    .card-green .card-label { color: #059669; }
    .card-purple .card-label { color: #7c3aed; }

    .card-calc {
      font-size: 14px;
      color: #64748b;
      margin-bottom: 4px;
      font-weight: 500;
    }
    .card-res {
      font-size: 18px;
      font-weight: 700;
    }
    .card-blue .card-res { color: #1d4ed8; }
    .card-green .card-res { color: #047857; }
    .card-purple .card-res { color: #6d28d9; }

    /* Assembly Box */
    .assembly-box {
      width: 100%;
      background: #ffffff;
      border: 2px solid #e2e8f0;
      border-radius: 12px;
      padding: 12px 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 10px;
      font-size: 22px;
      font-weight: 700;
      letter-spacing: -0.3px;
      transition: all 0.3s ease;
    }
    .assembly-box.complete {
      border-color: #0284c7;
      background: #f0f9ff;
      box-shadow: 0 4px 14px rgba(2, 132, 199, 0.15);
    }

    .term {
      padding: 2px 6px;
      border-radius: 6px;
      transition: opacity 0.25s ease, background 0.25s ease;
      opacity: 0.25;
    }
    .term.active {
      opacity: 1;
    }
    .term-blue { color: #1d4ed8; }
    .term-blue.active { background: #dbeafe; }
    .term-green { color: #047857; }
    .term-green.active { background: #d1fae5; }
    .term-purple { color: #6d28d9; }
    .term-purple.active { background: #ede9fe; }

    .op {
      color: #94a3b8;
      font-weight: 600;
      opacity: 0.3;
      transition: opacity 0.25s ease;
    }
    .op.active {
      opacity: 1;
      color: #475569;
    }

    /* Stepper Controls */
    .controls-row {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      margin-top: 4px;
    }

    .btn-step {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      color: #334155;
      font-size: 13px;
      font-weight: 600;
      padding: 6px 12px;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      transition: background 0.2s;
    }
    .btn-step:hover {
      background: #f1f5f9;
    }

    .dot-group {
      display: flex;
      gap: 6px;
      align-items: center;
      margin: 0 4px;
    }
    .step-dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: #cbd5e1;
      cursor: pointer;
      transition: background 0.2s;
    }
    .step-dot.active {
      background: #0284c7;
      transform: scale(1.2);
    }
  </style>
</head>
<body>
  <div class="main-wrap">
    
    <div class="problem-header">
      (<span class="t1">3x</span> + <span class="t3">4</span>)<sup>2</sup>
    </div>

    
    <div class="cards-grid">
      
      <div class="step-card card-blue active" id="card0" onclick="goToStep(0)">
        <div class="card-label">First Squared</div>
        <div class="card-calc">(3x)<sup>2</sup></div>
        <div class="card-res">9x<sup>2</sup></div>
      </div>

      
      <div class="step-card card-green" id="card1" onclick="goToStep(1)">
        <div class="card-label">Double Product</div>
        <div class="card-calc">2 · (3x) · (4)</div>
        <div class="card-res">24x</div>
      </div>

      
      <div class="step-card card-purple" id="card2" onclick="goToStep(2)">
        <div class="card-label">Last Squared</div>
        <div class="card-calc">4<sup>2</sup></div>
        <div class="card-res">16</div>
      </div>
    </div>

    
    <div class="assembly-box" id="assemblyBox">
      <span class="term term-blue active" id="term0">9x<sup>2</sup></span>
      <span class="op" id="op0">+</span>
      <span class="term term-green" id="term1">24x</span>
      <span class="op" id="op1">+</span>
      <span class="term term-purple" id="term2">16</span>
    </div>

    
    <div class="controls-row">
      <button class="btn-step" onclick="prevStep()">← Prev</button>
      <div class="dot-group">
        <div class="step-dot active" id="dot0" onclick="goToStep(0)"></div>
        <div class="step-dot" id="dot1" onclick="goToStep(1)"></div>
        <div class="step-dot" id="dot2" onclick="goToStep(2)"></div>
        <div class="step-dot" id="dot3" onclick="goToStep(3)"></div>
      </div>
      <button class="btn-step" onclick="nextStep()">Next →</button>
      <button class="btn-step" id="playBtn" onclick="togglePlay()">⏸</button>
    </div>
  </div>

  <script>
    let currentStep = 0;
    const totalSteps = 4; // 0: 1st term, 1: 2nd term, 2: 3rd term, 3: all combined
    let isPlaying = true;
    let timer = null;

    function renderStep() {
      const cards = [document.getElementById('card0'), document.getElementById('card1'), document.getElementById('card2')];
      const terms = [document.getElementById('term0'), document.getElementById('term1'), document.getElementById('term2')];
      const ops = [document.getElementById('op0'), document.getElementById('op1')];
      const dots = [document.getElementById('dot0'), document.getElementById('dot1'), document.getElementById('dot2'), document.getElementById('dot3')];
      const assemblyBox = document.getElementById('assemblyBox');

      dots.forEach((d, i) => d.classList.toggle('active', i === currentStep));

      if (currentStep === 3) {
        // Show everything assembled
        cards.forEach(c => c.classList.add('active'));
        terms.forEach(t => t.classList.add('active'));
        ops.forEach(o => o.classList.add('active'));
        assemblyBox.classList.add('complete');
      } else {
        cards.forEach((c, i) => c.classList.toggle('active', i <= currentStep));
        terms.forEach((t, i) => t.classList.toggle('active', i <= currentStep));
        ops[0].classList.toggle('active', currentStep >= 1);
        ops[1].classList.toggle('active', currentStep >= 2);
        assemblyBox.classList.remove('complete');
      }
    }

    function goToStep(idx) {
      currentStep = idx;
      renderStep();
    }

    function nextStep() {
      currentStep = (currentStep + 1) % totalSteps;
      renderStep();
    }

    function prevStep() {
      currentStep = (currentStep - 1 + totalSteps) % totalSteps;
      renderStep();
    }

    function togglePlay() {
      isPlaying = !isPlaying;
      document.getElementById('playBtn').textContent = isPlaying ? '⏸' : '▶';
      if (isPlaying) {
        startTimer();
      } else {
        clearInterval(timer);
      }
    }

    function startTimer() {
      clearInterval(timer);
      timer = setInterval(() => {
        if (isPlaying) {
          nextStep();
        }
      }, 3500);
    }

    renderStep();
    startTimer();
  </script>
</body>
</html>

Expanding Perfect Square Trinomials Algebraically

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Special Product Identities</title>
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      color: #1e293b;
      background: transparent;
      padding: 10px;
      display: flex;
      flex-direction: column;
      gap: 10px;
      max-width: 680px;
      margin: 0 auto;
    }

    /* Comparison Grid */
    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 10px;
    }

    @media (max-width: 480px) {
      .compare-grid {
        grid-template-columns: 1fr;
        gap: 8px;
      }
    }

    .formula-box {
      border-radius: 8px;
      padding: 10px 8px;
      text-align: center;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 6px;
    }

    .formula-box.sum-box {
      border: 1.5px solid #86efac;
      background: #f0fdf4;
    }

    .formula-box.diff-box {
      border: 1.5px solid #fdba74;
      background: #fff7ed;
    }

    .formula-header {
      font-size: 11px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      width: 100%;
      flex-wrap: wrap;
    }

    .sum-box .formula-header {
      color: #166534;
    }

    .diff-box .formula-header {
      color: #9a3412;
    }

    .badge {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 2px 7px;
      border-radius: 5px;
      font-size: 11px;
      font-weight: 800;
    }

    .badge-plus {
      background: #dcfce7;
      color: #15803d;
      border: 1px solid #86efac;
    }

    .badge-minus {
      background: #ffedd5;
      color: #c2410c;
      border: 1px solid #fdba74;
    }

    .math-eq {
      font-family: 'Cambria Math', 'KaTeX_Math', 'Times New Roman', Times, serif;
      font-size: 16px;
      line-height: 1.4;
      display: inline-block;
      text-align: center;
    }

    .math-eq i {
      font-style: italic;
      font-weight: 600;
      padding: 0 0.5px;
    }

    .math-eq sup {
      font-size: 0.72em;
      line-height: 0;
      position: relative;
      vertical-align: baseline;
      top: -0.45em;
      font-weight: 700;
      margin-left: 0.5px;
    }

    /* Color coding tokens */
    .val-a { color: #2563eb; }
    .val-b { color: #9333ea; }
    .highlight-mid-plus {
      background: #dcfce7;
      color: #15803d;
      padding: 1px 5px;
      border-radius: 4px;
      font-weight: 700;
      margin: 0 2px;
      display: inline-block;
    }

    .highlight-mid-minus {
      background: #ffedd5;
      color: #c2410c;
      padding: 1px 5px;
      border-radius: 4px;
      font-weight: 700;
      margin: 0 2px;
      display: inline-block;
    }

    /* Worked Example Section */
    .example-panel {
      background: #f8fafc;
      border: 1.5px solid #e2e8f0;
      border-radius: 8px;
      padding: 10px;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .panel-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 6px;
      font-size: 12px;
      font-weight: 700;
      color: #475569;
    }

    .target-title {
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .target-eq {
      font-family: 'Cambria Math', 'Times New Roman', serif;
      font-size: 14px;
      color: #0f172a;
      font-weight: bold;
    }

    .stepper-controls {
      display: flex;
      gap: 4px;
      align-items: center;
    }

    .step-btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      border-radius: 5px;
      padding: 3px 8px;
      font-size: 11px;
      font-weight: 600;
      color: #334155;
      cursor: pointer;
      transition: background-color 0.15s, color 0.15s, border-color 0.15s;
    }

    .step-btn:hover {
      border-color: #94a3b8;
      background: #f1f5f9;
    }

    .step-btn.active {
      background: #2563eb;
      color: #ffffff;
      border-color: #2563eb;
    }

    .step-display {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 6px;
      padding: 8px;
      min-height: 60px;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
    }

    .step-row {
      display: none;
      flex-direction: column;
      align-items: center;
      gap: 4px;
      width: 100%;
      text-align: center;
    }

    .step-row.active {
      display: flex;
    }

    .step-desc {
      font-size: 11px;
      font-weight: 600;
      color: #64748b;
    }

    .term-map {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      font-size: 13px;
      background: #f1f5f9;
      padding: 3px 10px;
      border-radius: 4px;
      font-family: 'Cambria Math', 'Times New Roman', serif;
    }

    .full-solution-preview {
      margin-top: 2px;
      padding-top: 6px;
      border-top: 1px dashed #cbd5e1;
      display: flex;
      justify-content: center;
      align-items: center;
      flex-wrap: wrap;
      gap: 6px;
      font-size: 12px;
      color: #64748b;
      font-weight: 600;
    }

    .full-solution-preview .math-eq {
      font-size: 13.5px;
      color: #0f172a;
      font-weight: normal;
    }
  </style>
</head>
<body>

  
  <div class="compare-grid">
    <div class="formula-box sum-box">
      <div class="formula-header">
        <span>Square of a Sum</span>
        <span class="badge badge-plus">+ 2ab</span>
      </div>
      <div class="math-eq">
        (<i>a</i> + <i>b</i>)<sup>2</sup> = <i>a</i><sup>2</sup> <span class="highlight-mid-plus">+ 2<i>ab</i></span> + <i>b</i><sup>2</sup>
      </div>
    </div>

    <div class="formula-box diff-box">
      <div class="formula-header">
        <span>Square of a Difference</span>
        <span class="badge badge-minus">− 2ab</span>
      </div>
      <div class="math-eq">
        (<i>a</i> − <i>b</i>)<sup>2</sup> = <i>a</i><sup>2</sup> <span class="highlight-mid-minus">− 2<i>ab</i></span> + <i>b</i><sup>2</sup>
      </div>
    </div>
  </div>

  
  <div class="example-panel">
    <div class="panel-header">
      <div class="target-title">
        <span>EXAMPLE:</span>
        <span class="target-eq">(5<i>x</i> − 2<i>y</i>)<sup>2</sup></span>
      </div>
      <div class="stepper-controls">
        <button type="button" class="step-btn active" data-step="0">1. Identify</button>
        <button type="button" class="step-btn" data-step="1">2. Substitute</button>
        <button type="button" class="step-btn" data-step="2">3. Simplify</button>
      </div>
    </div>

    <div class="step-display">
      
      <div class="step-row active" id="step-0">
        <div class="step-desc">Match with (<i>a</i> − <i>b</i>)<sup>2</sup> pattern:</div>
        <div class="term-map">
          <span class="val-a"><i>a</i> = 5<i>x</i></span>
          <span style="color:#94a3b8; font-weight: bold;">and</span>
          <span class="val-b"><i>b</i> = 2<i>y</i></span>
        </div>
      </div>

      
      <div class="step-row" id="step-1">
        <div class="step-desc">Substitute into <i>a</i><sup>2</sup> − 2<i>ab</i> + <i>b</i><sup>2</sup>:</div>
        <div class="math-eq">
          (<span class="val-a">5<i>x</i></span>)<sup>2</sup>
          <span class="highlight-mid-minus">− 2(<span class="val-a">5<i>x</i></span>)(<span class="val-b">2<i>y</i></span>)</span>
          + (<span class="val-b">2<i>y</i></span>)<sup>2</sup>
        </div>
      </div>

      
      <div class="step-row" id="step-2">
        <div class="step-desc">Calculate each simplified term:</div>
        <div class="math-eq">
          <span class="val-a" style="font-weight:700;">25<i>x</i><sup>2</sup></span>
          <span class="highlight-mid-minus">− 20<i>xy</i></span>
          + <span class="val-b" style="font-weight:700;">4<i>y</i><sup>2</sup></span>
        </div>
      </div>
    </div>

    
    <div class="full-solution-preview">
      <span>Summary:</span>
      <div class="math-eq">
        (5<i>x</i> − 2<i>y</i>)<sup>2</sup> = 25<i>x</i><sup>2</sup> − 20<i>xy</i> + 4<i>y</i><sup>2</sup>
      </div>
    </div>
  </div>

  <script>
    const buttons = document.querySelectorAll('.step-btn');
    const stepRows = [
      document.getElementById('step-0'),
      document.getElementById('step-1'),
      document.getElementById('step-2')
    ];

    buttons.forEach((btn, index) => {
      btn.addEventListener('click', () => {
        buttons.forEach((b, i) => b.classList.toggle('active', i === index));
        stepRows.forEach((row, i) => row.classList.toggle('active', i === index));
      });
    });
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, sans-serif;
    }

    body {
      background: transparent;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    /* Controls Bar */
    .controls {
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: #f1f5f9;
      padding: 6px 12px;
      border-radius: 8px;
      font-size: 14px;
      font-weight: 600;
    }

    .btn-group {
      display: flex;
      gap: 6px;
    }

    .x-btn {
      border: 1px solid #cbd5e1;
      background: #ffffff;
      color: #475569;
      padding: 4px 10px;
      border-radius: 6px;
      font-size: 13px;
      font-weight: 700;
      cursor: pointer;
      transition: background 0.2s, color 0.2s, border-color 0.2s;
    }

    .x-btn.active {
      background: #2563eb;
      color: #ffffff;
      border-color: #2563eb;
    }

    /* Proof Panels */
    .panel {
      border-radius: 10px;
      padding: 12px 14px;
      display: flex;
      flex-direction: column;
      gap: 8px;
      position: relative;
    }

    .panel-false {
      background: #fef2f2;
      border: 1.5px solid #fecaca;
    }

    .panel-true {
      background: #f0fdf4;
      border: 1.5px solid #bbf7d0;
    }

    .header-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      font-size: 16px;
      font-weight: 700;
    }

    .badge {
      display: inline-flex;
      align-items: center;
      gap: 4px;
      padding: 2px 8px;
      border-radius: 6px;
      font-size: 12px;
      font-weight: 800;
      letter-spacing: 0.5px;
      text-transform: uppercase;
    }

    .badge-false {
      background: #dc2626;
      color: #ffffff;
    }

    .badge-true {
      background: #16a34a;
      color: #ffffff;
    }

    .math-eq {
      font-family: "Cambria Math", "Times New Roman", serif;
      font-size: 17px;
      letter-spacing: 0.2px;
    }

    .strike {
      text-decoration: line-through;
      text-decoration-color: #dc2626;
      text-decoration-thickness: 2.5px;
      color: #991b1b;
    }

    .correct-eq {
      color: #166534;
    }

    .highlight-term {
      background: #bbf7d0;
      color: #14532d;
      padding: 1px 4px;
      border-radius: 4px;
      font-weight: 700;
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<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <title>Finding GCF of Monomials</title>
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    </div>

    
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      <div class="summary-res">
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Factoring Out Greatest Common Monomial and Binomial Factors

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Factoring Binomial GCF</title>
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      transition: background 0.2s ease, border-color 0.2s ease, color 0.2s ease;
    }

    .step-btn:hover {
      background: #f3f4f6;
    }

    .step-btn.active {
      background: #0284c7;
      border-color: #0284c7;
      color: #ffffff;
      box-shadow: 0 2px 4px rgba(2, 132, 199, 0.25);
    }

    .play-btn {
      background: #ffffff;
      border: 1px solid #d1d5db;
      border-radius: 50%;
      width: 30px;
      height: 30px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 12px;
      cursor: pointer;
      color: #1e2945;
      transition: background 0.2s ease;
    }

    .play-btn:hover {
      background: #f3f4f6;
    }

    /* Stage Area - sits directly on canvas */
    .stage-area {
      width: 100%;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 8px 4px;
    }

    .step-indicator-label {
      font-size: 13px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      color: #64748b;
      margin-bottom: 12px;
      text-align: center;
    }

    /* Equation Display */
    .equation {
      font-size: 26px;
      font-weight: 600;
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      justify-content: center;
      flex-wrap: wrap;
      gap: 6px;
      line-height: 1.4;
      text-align: center;
      min-height: 44px;
    }

    /* Badges */
    .badge-blue {
      background: #e0f2fe;
      color: #0284c7;
      border: 1.5px solid #38bdf8;
      border-radius: 8px;
      padding: 2px 8px;
      font-weight: 700;
      display: inline-block;
      transition: all 0.3s ease;
    }

    .badge-yellow {
      background: #fef3c7;
      color: #b45309;
      border: 1.5px solid #fcd34d;
      border-radius: 8px;
      padding: 2px 10px;
      font-weight: 800;
      display: inline-block;
      transition: all 0.3s ease;
    }

    .term {
      color: #1e2945;
    }

    .op {
      color: #64748b;
      margin: 0 2px;
    }

    /* Legend / Sub-note */
    .legend {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-size: 14px;
      font-weight: 600;
      color: #475569;
      margin-top: 12px;
      padding: 4px 8px;
      text-align: center;
      flex-wrap: wrap;
    }

    .arrow {
      color: #94a3b8;
      font-size: 14px;
      font-weight: 500;
    }

    @media (max-width: 420px) {
      body {
        padding: 8px;
      }
      .main-wrap {
        gap: 10px;
      }
      .equation {
        font-size: 20px;
        gap: 4px;
      }
      .badge-blue, .badge-yellow {
        padding: 1px 6px;
        border-radius: 6px;
      }
      .step-btn {
        padding: 4px 9px;
        font-size: 12px;
      }
      .legend {
        font-size: 13px;
        margin-top: 8px;
      }
    }
  </style>
</head>
<body>

<div class="main-wrap">
  
  <div class="stepper-nav">
    <button class="step-btn active" onclick="setStep(0)">1. GCF</button>
    <button class="step-btn" onclick="setStep(1)">2. Substitute [B]</button>
    <button class="step-btn" onclick="setStep(2)">3. Factor [B]</button>
    <button class="step-btn" onclick="setStep(3)">4. Result</button>
    <button class="play-btn" id="playBtn" onclick="togglePlay()" title="Play/Pause">⏸</button>
  </div>

  
  <div class="stage-area">
    <div class="step-indicator-label" id="stepLabel">Step 1: Identify Common Binomial</div>
    <div class="equation" id="equationContainer">
      
    </div>
    <div class="legend" id="legendContainer">
      
    </div>
  </div>
</div>

<script>
  const steps = [
    {
      label: "Step 1: Identify Common Binomial",
      html: `
        <span class="term">3x</span><span class="badge-blue">(x − 4)</span>
        <span class="op">+</span>
        <span class="term">7</span><span class="badge-blue">(x − 4)</span>
      `,
      legend: `<span class="badge-blue">(x − 4)</span> <span class="arrow">is the common factor</span>`
    },
    {
      label: "Step 2: Substitute [B]",
      html: `
        <span class="term">3x</span><span class="badge-yellow">[B]</span>
        <span class="op">+</span>
        <span class="term">7</span><span class="badge-yellow">[B]</span>
      `,
      legend: `<span class="badge-yellow">[B]</span> <span class="arrow">=</span> <span class="badge-blue">(x − 4)</span>`
    },
    {
      label: "Step 3: Factor Out [B]",
      html: `
        <span class="term">(3x + 7)</span><span class="badge-yellow">[B]</span>
      `,
      legend: `<span class="arrow">Distributive property in reverse</span>`
    },
    {
      label: "Step 4: Substitute Back",
      html: `
        <span class="term">(3x + 7)</span><span class="badge-blue">(x − 4)</span>
      `,
      legend: `<span class="badge-yellow">[B]</span> <span class="arrow">→</span> <span class="badge-blue">(x − 4)</span>`
    }
  ];

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  let timer = null;
  let isPlaying = true;

  function render() {
    const eq = document.getElementById('equationContainer');
    const lbl = document.getElementById('stepLabel');
    const leg = document.getElementById('legendContainer');
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    eq.innerHTML = steps[currentStep].html;
    leg.innerHTML = steps[currentStep].legend;

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      btn.classList.toggle('active', idx === currentStep);
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    currentStep = idx;
    render();
    if (isPlaying) {
      resetTimer();
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    currentStep = (currentStep + 1) % steps.length;
    render();
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  function resetTimer() {
    if (timer) clearInterval(timer);
    timer = setInterval(nextStep, 3500);
  }

  function togglePlay() {
    isPlaying = !isPlaying;
    const playBtn = document.getElementById('playBtn');
    if (isPlaying) {
      playBtn.textContent = '⏸';
      resetTimer();
    } else {
      playBtn.textContent = '▶';
      clearInterval(timer);
    }
  }

  render();
  resetTimer();
</script>

</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background: #f8fafc;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
    }

    /* Container */
    .flow-container {
      width: 100%;
      max-width: 580px;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    /* Controls Header */
    .controls-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 8px;
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 6px 12px;
    }
    .btn-group {
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .nav-btn {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      padding: 5px 10px;
      font-size: 13px;
      font-weight: 600;
      color: #334155;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      user-select: none;
      transition: background 0.2s, border-color 0.2s;
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    .nav-btn:hover {
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      border-color: #94a3b8;
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      background: #2563eb;
      color: #ffffff;
      border-color: #1d4ed8;
    }
    .nav-btn.primary:hover {
      background: #1d4ed8;
    }

    .dots-nav {
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .dot-btn {
      width: 24px;
      height: 24px;
      border-radius: 50%;
      border: 1px solid #cbd5e1;
      background: #ffffff;
      color: #64748b;
      font-size: 11px;
      font-weight: 700;
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      transition: all 0.2s ease;
    }
    .dot-btn:hover {
      border-color: #2563eb;
      color: #2563eb;
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    .dot-btn.active {
      background: #2563eb;
      border-color: #2563eb;
      color: #ffffff;
      box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.2);
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    /* Step Cards Stack */
    .steps-wrapper {
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .step-card {
      background: #ffffff;
      border: 1.5px solid #e2e8f0;
      border-radius: 12px;
      padding: 10px 14px;
      display: flex;
      flex-direction: column;
      gap: 6px;
      position: relative;
      transition: border-color 0.25s, box-shadow 0.25s, opacity 0.25s;
      cursor: pointer;
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      border-color: #2563eb;
      box-shadow: 0 4px 12px rgba(37, 99, 235, 0.08);
      opacity: 1;
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    .step-card.inactive {
      opacity: 0.55;
      border-color: #e2e8f0;
    }
    .step-card:hover {
      opacity: 0.95;
    }

    .step-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      font-size: 12px;
      font-weight: 700;
      color: #64748b;
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }
    .step-card.active .step-header {
      color: #2563eb;
    }

    .step-badge {
      background: #f1f5f9;
      color: #475569;
      padding: 2px 8px;
      border-radius: 12px;
      font-size: 11px;
      font-weight: 600;
    }
    .step-card.active .step-badge {
      background: #dbeafe;
      color: #1e40af;
    }

    /* Math expression display */
    .math-row {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 4px;
      font-size: 19px;
      font-weight: 700;
      font-family: 'Cambria Math', 'KaTeX_Main', serif, system-ui;
      padding: 4px 0;
      flex-wrap: wrap;
    }

    /* Token styling */
    .tok {
      padding: 2px 6px;
      border-radius: 6px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: all 0.2s;
    }
    .tok-blue {
      background: #dbeafe;
      color: #1e40af;
      border: 1px solid #93c5fd;
    }
    .tok-amber {
      background: #fef3c7;
      color: #92400e;
      border: 1px solid #fcd34d;
    }
    .tok-rose {
      background: #ffe4e6;
      color: #be123c;
      border: 1px solid #fda4af;
    }
    .tok-purple {
      background: #f3e8ff;
      color: #6b21a8;
      border: 1px solid #d8b4fe;
    }
    .tok-green {
      background: #dcfce7;
      color: #166534;
      border: 1px solid #86efac;
    }

    /* Arrow Connector */
    .arrow-divider {
      display: flex;
      align-items: center;
      justify-content: center;
      color: #94a3b8;
      font-size: 13px;
      font-weight: 700;
      margin: -4px 0;
    }

    /* Mini Action Callout */
    .action-note {
      font-size: 12px;
      color: #475569;
      text-align: center;
      font-weight: 500;
      font-family: system-ui, sans-serif;
    }

    @media (max-width: 420px) {
      .math-row {
        font-size: 16px;
      }
      .dot-btn {
        width: 22px;
        height: 22px;
        font-size: 10px;
      }
      .nav-btn {
        padding: 4px 8px;
        font-size: 12px;
      }
    }
  </style>
</head>
<body>
  <div class="flow-container">
    
    <div class="controls-bar">
      <div class="btn-group">
        <button id="playBtn" class="nav-btn primary" onclick="togglePlay()">
          <span id="playIcon">⏸</span> <span id="playText">Pause</span>
        </button>
      </div>

      <div class="dots-nav">
        <button class="dot-btn active" onclick="selectStep(0)">1</button>
        <button class="dot-btn" onclick="selectStep(1)">2</button>
        <button class="dot-btn" onclick="selectStep(2)">3</button>
      </div>

      <div class="btn-group">
        <button class="nav-btn" onclick="prevStep()">◀</button>
        <button class="nav-btn" onclick="nextStep()">▶</button>
      </div>
    </div>

    
    <div id="card0" class="step-card active" onclick="selectStep(0)">
      <div class="step-header">
        <span>Step 1: Identify Opposite Binomial</span>
        <span class="step-badge">(2 − x) = −(x − 2)</span>
      </div>
      <div class="math-row">
        <span>5x</span>
        <span class="tok tok-blue">(x − 2)</span>
        <span>+ 3</span>
        <span class="tok tok-amber">[ −(x − 2) ]</span>
      </div>
      <div class="action-note">Rewrite <b>(2 − x)</b> as <b>−(x − 2)</b></div>
    </div>

    <div class="arrow-divider">↓</div>

    
    <div id="card1" class="step-card inactive" onclick="selectStep(1)">
      <div class="step-header">
        <span>Step 2: Multiply Negative Sign</span>
        <span class="step-badge">+3 · (−) = −3</span>
      </div>
      <div class="math-row">
        <span class="tok tok-purple">5x</span>
        <span class="tok tok-blue">(x − 2)</span>
        <span class="tok tok-rose">− 3</span>
        <span class="tok tok-blue">(x − 2)</span>
      </div>
      <div class="action-note">Move the negative into <b>+3</b> → becomes <b>−3</b></div>
    </div>

    <div class="arrow-divider">↓</div>

    
    <div id="card2" class="step-card inactive" onclick="selectStep(2)">
      <div class="step-header">
        <span>Step 3: Factor Out Common Binomial</span>
        <span class="step-badge">Result</span>
      </div>
      <div class="math-row">
        <span class="tok tok-blue">(x − 2)</span>
        <span class="tok tok-green">(5x − 3)</span>
      </div>
      <div class="action-note">Pull out <b>(x − 2)</b> and group remaining terms</div>
    </div>
  </div>

  <script>
    let currentStep = 0;
    const totalSteps = 3;
    let isPlaying = true;
    let timer = null;

    function updateUI() {
      // Update cards
      for (let i = 0; i < totalSteps; i++) {
        const card = document.getElementById('card' + i);
        if (card) {
          if (i === currentStep) {
            card.classList.remove('inactive');
            card.classList.add('active');
          } else {
            card.classList.remove('active');
            card.classList.add('inactive');
          }
        }
      }

      // Update dots
      const dots = document.querySelectorAll('.dot-btn');
      dots.forEach((dot, idx) => {
        if (idx === currentStep) {
          dot.classList.add('active');
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          dot.classList.remove('active');
        }
      });
    }

    function selectStep(stepIndex) {
      currentStep = stepIndex;
      updateUI();
      resetTimer();
    }

    function nextStep() {
      currentStep = (currentStep + 1) % totalSteps;
      updateUI();
      resetTimer();
    }

    function prevStep() {
      currentStep = (currentStep - 1 + totalSteps) % totalSteps;
      updateUI();
      resetTimer();
    }

    function togglePlay() {
      isPlaying = !isPlaying;
      const playIcon = document.getElementById('playIcon');
      const playText = document.getElementById('playText');
      const playBtn = document.getElementById('playBtn');

      if (isPlaying) {
        playIcon.textContent = '⏸';
        playText.textContent = 'Pause';
        playBtn.classList.add('primary');
        startTimer();
      } else {
        playIcon.textContent = '▶';
        playText.textContent = 'Play';
        playBtn.classList.remove('primary');
        stopTimer();
      }
    }

    function startTimer() {
      stopTimer();
      timer = setInterval(() => {
        currentStep = (currentStep + 1) % totalSteps;
        updateUI();
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    }

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      if (timer) {
        clearInterval(timer);
        timer = null;
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    }

    function resetTimer() {
      if (isPlaying) {
        startTimer();
      }
    }

    // Initialize on load
    startTimer();
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Distribution vs Factoring Area Model</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      background-color: #f8f9fa;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100vh;
      padding: 12px 8px;
    }

    .controls {
      display: flex;
      gap: 8px;
      margin-bottom: 12px;
      z-index: 10;
      flex-wrap: wrap;
      justify-content: center;
    }

    .btn-tab {
      background: #ffffff;
      border: 1.5px solid #cbd5e1;
      color: #1e2945;
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
      transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
    }

    .btn-tab:hover {
      background: #f1f5f9;
    }

    .btn-tab.active-blue {
      background: #2563eb;
      color: #ffffff;
      border-color: #2563eb;
    }

    .btn-tab.active-green {
      background: #059669;
      color: #ffffff;
      border-color: #059669;
    }

    .btn-tab.active-all {
      background: #1e2945;
      color: #ffffff;
      border-color: #1e2945;
    }

    .svg-container {
      width: 100%;
      max-width: 500px;
      display: flex;
      justify-content: center;
    }

    svg {
      width: 100%;
      height: auto;
      display: block;
      user-select: none;
      overflow: visible;
    }

    .panel-box {
      fill: #ffffff;
      stroke: #e2e8f0;
      stroke-width: 1.5;
      rx: 10px;
    }

    .section-group {
      transition: opacity 0.3s ease;
    }

    .dimmed {
      opacity: 0.22;
    }

    .math-italic {
      font-family: "Cambria Math", "KaTeX_Math", "Times New Roman", Georgia, serif;
      font-style: italic;
    }

    .math-regular {
      font-family: system-ui, sans-serif;
      font-style: normal;
    }

    .flow-arrow-right {
      animation: pulseRight 2.2s infinite ease-in-out;
    }

    .flow-arrow-left {
      animation: pulseLeft 2.2s infinite ease-in-out;
    }

    @keyframes pulseRight {
      0%, 100% { transform: translateX(0); }
      50% { transform: translateX(3px); }
    }

    @keyframes pulseLeft {
      0%, 100% { transform: translateX(0); }
      50% { transform: translateX(-3px); }
    }
  </style>
</head>
<body>

  <div class="controls" role="group" aria-label="Diagram display mode">
    <button class="btn-tab active-all" id="btnAll" onclick="setMode('all')">Compare Both</button>
    <button class="btn-tab" id="btnDist" onclick="setMode('dist')">Distribution →</button>
    <button class="btn-tab" id="btnFact" onclick="setMode('fact')">← Factoring</button>
  </div>

  <div class="svg-container">
    <svg viewBox="0 0 490 306" aria-label="Distribution and Factoring Area Model Comparison">
      <defs>
        
        <marker id="arrow-blue" viewBox="0 0 10 10" refX="7" refY="5" markerWidth="6" markerHeight="6" orient="auto">
          <path d="M 1 2 L 8 5 L 1 8 Z" fill="#2563eb" />
        </marker>

        
        <marker id="arrow-green-left" viewBox="0 0 10 10" refX="3" refY="5" markerWidth="6" markerHeight="6" orient="auto">
          <path d="M 9 2 L 2 5 L 9 8 Z" fill="#059669" />
        </marker>
      </defs>

      
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        <rect class="panel-box" x="8" y="8" width="474" height="138" />

        
        <rect x="20" y="18" width="132" height="22" rx="11" fill="#eff6ff" stroke="#bfdbfe" stroke-width="1"/>
        <text x="86" y="33" fill="#1d4ed8" font-size="11" font-weight="700" text-anchor="middle" letter-spacing="0.5">DISTRIBUTION →</text>

        
        <g transform="translate(24, 88)">
          <text font-size="19" font-weight="700" fill="#1e2945">
            <tspan class="math-italic" fill="#2563eb">a</tspan><tspan class="math-regular">(</tspan><tspan class="math-italic">b</tspan><tspan class="math-regular"> + </tspan><tspan class="math-italic">c</tspan><tspan class="math-regular">)</tspan>
          </text>
        </g>

        
        <g class="flow-arrow-right">
          <text x="135" y="73" fill="#2563eb" font-size="9.5" font-weight="700" text-anchor="middle">Multiply</text>
          <line x1="112" y1="82" x2="154" y2="82" stroke="#2563eb" stroke-width="2.5" stroke-linecap="round" marker-end="url(#arrow-blue)" />
        </g>

        
        <g transform="translate(182, 44)">
          
          <text x="-12" y="42" font-size="16" font-weight="700" fill="#2563eb" text-anchor="middle" class="math-italic">a</text>
          <text x="36" y="-7" font-size="15" font-weight="700" fill="#1e2945" text-anchor="middle" class="math-italic">b</text>
          <text x="108" y="-7" font-size="15" font-weight="700" fill="#1e2945" text-anchor="middle" class="math-italic">c</text>

          
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          <text x="36" y="38" font-size="16" font-weight="700" fill="#1e3a8a" text-anchor="middle" class="math-italic">ab</text>

          
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          <text x="108" y="38" font-size="16" font-weight="700" fill="#1e3a8a" text-anchor="middle" class="math-italic">ac</text>
        </g>

        
        <g class="flow-arrow-right">
          <text x="352" y="73" fill="#2563eb" font-size="9.5" font-weight="700" text-anchor="middle">Total Area</text>
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        </g>

        
        <g transform="translate(382, 88)">
          <text font-size="18" font-weight="700" fill="#1e2945">
            <tspan class="math-regular">= </tspan><tspan class="math-italic">ab</tspan><tspan class="math-regular"> + </tspan><tspan class="math-italic">ac</tspan>
          </text>
        </g>
      </g>

      
      <g id="secFact" class="section-group">
        
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        <text x="79" y="181" fill="#047857" font-size="11" font-weight="700" text-anchor="middle" letter-spacing="0.5">← FACTORING</text>

        
        <g transform="translate(24, 236)">
          <text font-size="19" font-weight="700" fill="#1e2945">
            <tspan class="math-italic" fill="#059669">a</tspan><tspan class="math-regular">(</tspan><tspan class="math-italic">b</tspan><tspan class="math-regular"> + </tspan><tspan class="math-italic">c</tspan><tspan class="math-regular">)</tspan>
          </text>
        </g>

        
        <g class="flow-arrow-left">
          <text x="135" y="221" fill="#059669" font-size="9.5" font-weight="700" text-anchor="middle">Group</text>
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          <text x="108" y="38" font-size="16" font-weight="700" fill="#065f46" text-anchor="middle" class="math-italic">ac</text>

          
          <text x="-12" y="42" font-size="16" font-weight="700" fill="#059669" text-anchor="middle" class="math-italic">a</text>
          <text x="36" y="-7" font-size="15" font-weight="700" fill="#1e2945" text-anchor="middle" class="math-italic">b</text>
          <text x="108" y="-7" font-size="15" font-weight="700" fill="#1e2945" text-anchor="middle" class="math-italic">c</text>
        </g>

        
        <g class="flow-arrow-left">
          <text x="352" y="221" fill="#059669" font-size="9.5" font-weight="700" text-anchor="middle">Find GCF</text>
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        </g>

        
        <g transform="translate(382, 236)">
          <text font-size="18" font-weight="700" fill="#1e2945">
            <tspan class="math-italic">ab</tspan><tspan class="math-regular"> + </tspan><tspan class="math-italic">ac</tspan>
          </text>
        </g>
      </g>
    </svg>
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        btnFact.classList.add('active-green');
        secDist.classList.add('dimmed');
        secFact.classList.remove('dimmed');
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</body>
</html>

OGM.10.ALG.3

Aligned learning resources

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