Which expression is equivalent to 15x – 2(3x + 6)? ! ! a. 3(3x + 4) b. 3(3x - 4) c. 9x + 12 d. 10x - 12

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.