Let g be a function defined for all reals. which of the following conditions is not sufficient to guarantee that g has an inverse function?
a. g is strictly decreasing
b. g is strictly increasing
c. g is symmetric about the origin
d. g is one-to-one

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.