SSS Similarity Theorem. By definition, two triangles are similar if all their corresponding angles are congruent and their corresponding sides are proportional. ... SSS Similarity Theorem: If all three pairs of corresponding sides of two triangles are proportional, then the two triangles are similar.
Isolate the variable by subtracting 8x from both sides to get -4x = -1. multiply both sides by -1 to get 4x = 1. divide both sides by 4 to get x = 1/4.