Equal Triangles Small 320×130 Medium 640×260 Large 1024×416 Download Tiff Original 2400×975 | (105.7 KB) Description Illustration used to show that two triangles are equal if the three sides of one are equal respectively to the three sides of the other. Keywords congruent, equal triangles, geometric proof, triangle Galleries Geometric Theorems and Proofs Source: C. A. Hart & Daniel D. Feldman Plane And Solid Geometry (New York: American Book Company, 1911) 34