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High school geometry

Not feeling ready for this? Check out Get ready for Geometry.

Performing transformations

Intro to Euclidean geometry: Performing transformationsIntroduction to rigid transformations: Performing transformationsTranslations: Performing transformations
Rotations: Performing transformationsReflections: Performing transformationsDilations: Performing transformations

Transformation properties and proofs

Rigid transformations overview: Transformation properties and proofsDilation preserved properties: Transformation properties and proofsProperties & definitions of transformations: Transformation properties and proofs
Symmetry: Transformation properties and proofsProofs with transformations: Transformation properties and proofs

Congruence

Transformations & congruence: CongruenceTriangle congruence from transformations: CongruenceCongruent triangles: CongruenceTheorems concerning triangle properties: Congruence
Working with triangles: CongruenceTheorems concerning quadrilateral properties: CongruenceProofs of general theorems: CongruenceConstructing lines & angles: Congruence

Similarity

Definitions of similarity: SimilarityIntroduction to triangle similarity: SimilaritySolving similar triangles: Similarity
Angle bisector theorem: SimilaritySolving problems with similar & congruent triangles: SimilarityProving relationships using similarity: SimilaritySolving modeling problems with similar & congruent triangles: Similarity

Right triangles & trigonometry

Pythagorean theorem: Right triangles & trigonometryPythagorean theorem proofs: Right triangles & trigonometrySpecial right triangles: Right triangles & trigonometryRatios in right triangles: Right triangles & trigonometry
Introduction to the trigonometric ratios: Right triangles & trigonometrySolving for a side in a right triangle using the trigonometric ratios: Right triangles & trigonometrySolving for an angle in a right triangle using the trigonometric ratios: Right triangles & trigonometrySine & cosine of complementary angles: Right triangles & trigonometryModeling with right triangles: Right triangles & trigonometry

Analytic geometry

Distance and midpoints: Analytic geometryDividing line segments: Analytic geometryProblem solving with distance on the coordinate plane: Analytic geometry
Parallel & perpendicular lines on the coordinate plane: Analytic geometryEquations of parallel & perpendicular lines: Analytic geometry

Conic sections

Graphs of circles intro: Conic sectionsStandard equation of a circle: Conic sectionsExpanded equation of a circle: Conic sections
Focus and directrix of a parabola: Conic sections

Circles

Circle basics: CirclesArc measure: CirclesArc length (from degrees): CirclesIntroduction to radians: CirclesArc length (from radians): CirclesSectors: Circles
Inscribed angles: CirclesInscribed shapes problem solving: CirclesProofs with inscribed shapes: CirclesProperties of tangents: CirclesConstructing regular polygons inscribed in circles: CirclesConstructing circumcircles & incircles: CirclesConstructing a line tangent to a circle: Circles

Solid geometry

2D vs. 3D objects: Solid geometryCavalieri's principle and dissection methods: Solid geometryVolume and surface area: Solid geometry
Density: Solid geometry

Course challenge

Test your knowledge of the skills in this course. Have a test coming up? The Course challenge can help you understand what you need to review.

Review articles

Right triangle trigonometry review
Volume formulas review
Special right triangles review
Triangle similarity review
Laws of sines and cosines review
Community questions