Richard has 5 things on his to do list next week: doing laundry, returning library books, visiting the dentist, getting a car wash, and going hiking. if none of them has a priority, how many different ways can Richard get things done on his to do list

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.