G.GSR.5.3

Use the properties of similarity transformations to establish criterion for two triangles to be similar. Use similarity criteria for triangles to solve problems and to prove relationships in geometric figures.

Khan Academy Resources
Triangle similarity reviewAngle-angle triangle similarity criterionTriangle congruence reviewDetermine congruent trianglesFind angles in congruent trianglesSolve triangles: angle bisector theoremDetermine similar triangles: AnglesSpecial right trianglesDetermine similar triangles: SSSSolve similar triangles (basic)Solve similar triangles (advanced)Use similar trianglesProve triangle similarityJustify constructionsUse ratios in right trianglesDilations: scale factorDilate trianglesDilate pointsProve triangle propertiesProve parallelogram propertiesSimilarity & transformationsProve triangle congruenceDilations and propertiesDetermining congruent trianglesGeometry proof problem: congruent segmentsGeometry proof problem: midpointFinding angles in isosceles triangles (example 2)Finding angles in isosceles trianglesCorresponding angles in congruent trianglesTriangle similarity postulates/criteriaSolving similar trianglesIntro to triangle similarityDetermining similar trianglesSolving similar triangles: same side plays different rolesChallenging similarity problemUsing similar & congruent triangles30-60-90 triangle example problemUsing the angle bisector theoremGeometry proof problem: squared circleDilating shapes: expandingDilations introDilations: scale factorDilating shapes: shrinking by 1/2Calculating angle measures to verify congruenceGeometry word problem: Earth & Moon radiiGeometry word problem: a perfect pool shotDilating pointsProving triangle congruenceGeometry word problem: the golden ratioSimilar shapes & transformations
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