Under which angle conditions could a triangle exsist

How many solutions does the nonlinear system of equations graphed bellow have?

What are the solutions of the system? solve by graphing. y = -x^2 - 3x + 2 y = -2x + 2

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.