https://www.khanacademy.org/math/geometry/hs-geo-trig/hs-geo-trig-ratios-intro/v/similarity-to-define-sine-cosine-and-tangent 2021-06-30T17:32:38Z Triangle similarity & the trigonometric ratios Sal explains how the trigonometric ratios are derived from triangle similarity considerations. Sal Khan video https://cdn.kastatic.org/googleusercontent/J9lnSKMAAwcdbUhOC5YT3pprGnuQROHxnqLGq_xtObAWFo8DrHqrLKaZWUOk_YJcyba1ytEJ-krfQjKw14IOdV48 Triangle similarity & the trigonometric ratios Sal explains how the trigonometric ratios are derived from triangle similarity considerations. https://cdn.kastatic.org/ka-youtube-converted/QuZMXVJNLCo.mp4/QuZMXVJNLCo.mp4 536 Similarity and congruency https://www.khanacademy.org/math/geometry/hs-geo-similarity/hs-geo-triangle-similarity-intro/e/similar_triangles_1 2025-12-28T12:11:43.202987517Z Determine similar triangles: Angles Given two triangles with some of their angle measures, determine whether the triangles are similar or not. Igor Terzic exercise https://www.khanacademy.org/math/geometry/hs-geo-congruence/xff63fac4:hs-geo-congruent-triangles/v/finding-congruent-triangles 2021-02-16T16:08:13Z Determining congruent triangles Sal uses the SSS, ASA, SAS, and AAS postulates to find congruent triangles. Sal Khan video https://cdn.kastatic.org/googleusercontent/ZmHWOvQQlpl4g9566EPjogzNfwnGHGWEnq1elLsBPxGams1q0U7rIo-JObb-PuZc82wH84zHkljj7CFSVPN04F4 Determining congruent triangles Sal uses the SSS, ASA, SAS, and AAS postulates to find congruent triangles. https://cdn.kastatic.org/ka-youtube-converted/d5UCZ9hO8X4.mp4/d5UCZ9hO8X4.mp4 448 Similarity and congruency https://www.khanacademy.org/math/cambridge-o-level-mathematics-4024/x3f4c73d082a798eb:geometry/x3f4c73d082a798eb:similarity-and-congruency/e/v2-congruence-similarity-and-angle-relationships-2 2023-12-04T17:55:05.230178085Z Congruence, similarity, and angle relationships: medium Congruence, similarity, and angle relationships: medium Duo Yang exercise https://www.khanacademy.org/math/cambridge-o-level-mathematics-4024/x3f4c73d082a798eb:geometry/x3f4c73d082a798eb:similarity-and-congruency/a/v2-sat-lesson-congruence-similarity-and-angle-relationships 2022-10-18T02:23:40.2192308Z Congruence, similarity, and angle relationships | Lesson A guide to congruence, similarity, and angle relationships on the digital SAT article https://www.khanacademy.org/math/cc-seventh-grade-math/x6b17ba59:scale-drawings/scale-copies/v/identifying-scale-factors-example 2022-10-06T11:16:59.256015857Z Identifying scale factor in drawings Identify the scale factor used to create a scale copy. video https://cdn.kastatic.org/googleusercontent/Ka4-T5hesx7LsE0svYgP73a5K0AP-dyuqENzBEJCDFelGOeBU41qukthcbeY3PknPwcPbVDEffAcI4w0a3elNxOECg Identifying scale factor in drawings Identify the scale factor used to create a scale copy. https://cdn.kastatic.org/ka-youtube-converted/ZeY1mgog2YQ.mp4/ZeY1mgog2YQ.mp4 86 Similarity and congruency https://www.khanacademy.org/math/cc-seventh-grade-math/x6b17ba59:scale-drawings/scale-copies/e/scale-factor-in-scale-drawings 2026-01-15T23:20:44.102426557Z Identify scale factor in scale drawings Identify scale factor in scale copies of figures.  Lindsay exercise https://www.khanacademy.org/math/cc-seventh-grade-math/x6b17ba59:scale-drawings/cc-7th-scale-drawings/v/scale-factors-and-area 2022-10-06T11:16:59.256015857Z Scale factors and area Sal explore how scale factor affects the area of a scaled figure. video https://cdn.kastatic.org/googleusercontent/4Z5I3bwraipywrBBklLVas4eUV6u4yYScHpoeikquLFy8NEwdCc0JS7wtmUPYm19gAE3gYFfHCfvCPX8rpyx1pT7 Scale factors and area Sal explore how scale factor affects the area of a scaled figure. https://cdn.kastatic.org/ka-youtube-converted/h-qwno7n5F4.mp4/h-qwno7n5F4.mp4 364 Similarity and congruency https://www.khanacademy.org/math/cc-seventh-grade-math/x6b17ba59:scale-drawings/cc-7th-scale-drawings/e/relate-scale-drawings-to-area 2026-03-26T21:40:53.527314638Z Relate scale drawings to area Understand how creating a scale copy of a figure affects the area of the figure. Lindsay exercise