Pizza shack discounts the regular selling price on the purchase of 3 or more pizzas by 15%. what is the sale price on three pizzas that regularly cost, $9.75, $15.75, and $19.75?

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.