Charmaine plans to attend college in 4 years. She will need $19,200 for the first-year cost. Her uncle gave her a special gift of $12,000 to use toward the cost. How much must Charmaine save each month to have enough for the first-year cost?

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.