Areas Of Two Similar Triangles Theorem 1: The ratio of the areas of two similar triangles are equal to the ratio of the squares of any two corresponding sides. Given: Two triangles ABC and DEF such that ∆ABC ~ ∆DEF. To Prove: Construction: Draw AL ⊥ BC and DM ⊥ EF. Proof: Since similar triangles are equiangular and their corresponding sides are proportional. … [Read more...] about Areas Of Two Similar Triangles