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9th Grade · Math · Open Global Math
Advanced Mathematical Problem-Solving and Justification
Track 1 of 8 · 7 lessons
7 lessons
Analyze complex problem conditions, formulate multi-step strategies, verify solutions using multiple representations, and justify mathematical reasoning with formal precision.
Featured Diagrams
- 1Analyzing Given Conditions and Identifying ConstraintsUp nextStart
- 2Formulating Multi-Step Solution PathwaysPremiumNot started yet
- 3Communicating Geometric Reasoning with Precise LanguageNot started yet
- 4Justifying Algebraic Transformations with Formal PropertiesNot started yet
- 5Verifying Word Problem Answers with Inverse ModelsNot started yet
- 6Evaluating Multiple Problem-Solving StrategiesNot started yet
- 7Translating Insights Across Multiple RepresentationsNot started yet
Advanced Rational Expressions and Quotient-Remainder Forms
Track 2 of 8 · 5 lessons
5 lessons
Simplify complex fractions, rewrite improper rational expressions into quotient-remainder form, and solve applied rational modeling problems.
Featured Diagrams
- 1Simplifying Complex Fractions Using LCD MultiplicationUp nextStart
- 2Simplifying Complex Fractions by Division of TermsPremiumNot started yet
- 3Rewriting Improper Rational Expressions in Quotient-Remainder FormNot started yet
- 4Identifying Vertical and Horizontal Asymptotes from Rational FormsNot started yet
- 5Rational Functions and Their Real-World ApplicationsNot started yet
Arithmetic and Geometric Sequences and Series
Track 3 of 8 · 9 lessons
9 lessons
Represent arithmetic and geometric sequences recursively and explicitly, link to linear/exponential growth, and derive and evaluate geometric series.
Featured Diagrams
- 1Sequences as Functions on Discrete DomainsUp nextStart
- 2Recursive Formulas for Arithmetic SequencesPremiumNot started yet
- 3Explicit Formulas for Arithmetic SequencesNot started yet
- 4Connecting Arithmetic Sequences to Linear GrowthNot started yet
- 5Recursive Formulas for Geometric SequencesNot started yet
- 6Explicit Formulas for Geometric SequencesNot started yet
- 7Connecting Geometric Sequences to Exponential GrowthNot started yet
- 8Deriving the Sum Formula for Finite Geometric SeriesNot started yet
- 9Evaluating Finite Geometric Series in Applied ContextsNot started yet
Bivariate Data, Correlation, and Regression Modeling
Track 4 of 8 · 8 lessons
8 lessons
Analyze bivariate data, calculate and interpret Pearson's r, fit linear, quadratic, and exponential models, and evaluate predictions.
Featured Diagrams
- 1Bivariate Data: Scatter Diagrams and Linear CorrelationUp nextStart
- 2Calculating and Interpreting the Pearson Correlation CoefficientPremiumNot started yet
- 3Distinguishing Correlation from Causation and Lurking VariablesNot started yet
- 4Fitting Least-Squares Linear Regression Lines and Analyzing ResidualsNot started yet
- 5Making Predictions from Linear ModelsNot started yet
- 6Identifying Linear, Quadratic, and Exponential Patterns in Scatter PlotsNot started yet
- 7Fitting and Interpreting Quadratic Regression ModelsNot started yet
- 8Fitting and Interpreting Exponential Regression ModelsNot started yet
Cartographic Map Projections and Metric Distortions
Track 5 of 8 · 7 lessons
7 lessons
Analyze how mapping a 3D spherical surface onto 2D planes induces metric distortions in angles, scale, and surface area across cylindrical, conic, and azimuthal projections.
Featured Diagrams
- 1Geometry of the Sphere, Great Circles, and Gaussian CurvatureUp nextStart
- 2Cylindrical Projections and Areal Distortion: The Mercator MapPremiumNot started yet
- 3Equal-Area Cylindrical Projections and Angular DistortionNot started yet
- 4Conic Projections and Mid-Latitude Metric AccuracyNot started yet
- 5Azimuthal Projections, Polar Navigation, and Great-Circle RoutesNot started yet
- 6Tissot's Indicatrix: Quantifying Local Metric DistortionNot started yet
- 7Evaluating and Selecting Map Projections for Geospatial ProblemsNot started yet
Cavalieri's Principle and Spatial Measurement of 3D Solids
Track 6 of 8 · 10 lessons
10 lessons
Use Cavalieri's principle and solid decomposition methods to derive and calculate surface areas and volumes of prisms, cylinders, pyramids, cones, spheres, and composite solids.
Featured Diagrams
- 1Understanding Cavalieri's Principle for 2D and 3D FiguresUp nextStart
- 2Volume and Surface Area of Right and Oblique PrismsPremiumNot started yet
- 3Volume and Surface Area of Right and Oblique CylindersNot started yet
- 4Deriving Pyramid Volume Through Cube DecompositionNot started yet
- 5Deriving the Curved Surface Area of a Cone Using a SectorNot started yet
- 6Surface Area of Pyramids and ConesNot started yet
- 7Deriving the Volume and Surface Area of a Sphere Using Cavalieri's PrincipleNot started yet
- 8Comparing Volumes of Cylinders, Cones, and SpheresNot started yet
- 9Volume and Surface Area of FrustumsNot started yet
- 10Word Problems: Surface Areas and Volumes of Combined SolidsNot started yet
Circle Metrics: Arc Length, Sectors, and Circular Segments
Track 7 of 8 · 5 lessons
5 lessons
Derive and calculate arc length, sector area, and circular segment area in degrees and radians, and solve composite geometric problems.
Featured Diagrams
- 1Arc Length and Sector AreaUp nextStart
- 2Finding the Central Angle from Arc Length or Sector AreaPremiumNot started yet
- 3Calculating the Area of Circular SegmentsNot started yet
- 4Perimeter of Sectors and Composite Circular RegionsNot started yet
- 5Mixed Arc Length and Sector Area ProblemsNot started yet
Circle Theorems: Chords, Angles, and Cyclic Quadrilaterals
Track 8 of 8 · 7 lessons
7 lessons
Prove circle theorems involving chords, central and inscribed angles, angles in the same segment, and cyclic quadrilaterals.
Featured Diagrams
- 1Perpendicular Bisector of a Chord Theorem and ProofUp nextStart
- 2Equidistant Chords and Chords of Equal LengthPremiumNot started yet
- 3Inscribed Angle Theorem and CorollariesNot started yet
- 4Circle Theorems: Angles in the Same SegmentNot started yet
- 5Angle in a Semicircle: Thales' Circle TheoremNot started yet
- 6Circle Theorems: Cyclic QuadrilateralsNot started yet
- 7Converse: If Opposite Angles Are Supplementary, Points Lie on a CircleNot started yet