“Snowhill Mountain Resort charges a $20 flat rate for ski rental plus $6 per hour. Ben has no more than $86 to spend on a day of skiing. How man hours can Ben ski with the money he has available?”

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.