Underline the hypothesis once and the conclusion twice. The transform the conditional statement into if-then form. 1. Right angles measure congruent. If-then form
2. Acute angles measure less than 90°. If-then form
3. The sum of two even numbers is even. If-then form

Given: ae ≅ ce ; de ≅ be prove: abcd is a parallelogram. we have that ab || dc. by a similar argument used to prove that △aeb ≅ △ced, we can show that △ ≅ △ceb by. so, ∠cad ≅ ∠ by cpctc. therefore, ad || bc by the converse of the theorem. since both pair of opposite sides are parallel, quadrilateral abcd is a parallelogram.