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Circle Foundations, Pi, Circumference, and Arcs

7th Grade · Math · Open Global Math

9 lessons

Goal

Define pi, calculate circumference and arc length, and analyze chords, tangents, and central and inscribed angles.

9 lessons
0 of 9 done
  1. Defining Circles, Radii, Diameters, and PiUp next
  2. Calculating Circumference Using Exact and Approximate Values of PiNot started yet
  3. Central Angles and Arc MeasureNot started yet
  4. Calculating Arc Length as a Fraction of CircumferenceNot started yet
  5. Chords and Perpendicular Bisector Properties in CirclesNot started yet
  6. Tangent Lines and Radius PerpendicularityYou are here
  7. Equal Tangents from an External Point: Theorem and ProofNot started yet
  8. Inscribed Angle Theorem and CorollariesNot started yet
  9. Angles Formed by Tangents, Secants, and ChordsNot started yet
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Learning standards covered

GlobalOGM.8.GEO.4Open Global Math Standards 2026™ · 7th Grade

Understand circles, define pi (pi = C/d), derive formulas for circumference and area of circles and sectors/arcs, solve related composite area problems, and explore fundamental circle properties (chords, tangents, central/inscribed angles).