The ratio of North American Butterflies to South American butterflies at a butterfly park is 7:5. The ratio of South American butterflies to European butterflies is 5:2. There are 70 North American butterflies at the butterfly park.

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.