Which is a valid prediction about the continuous function f(x)?
a. f(x) ≥ 0 over the interval [5, ∞).
b. f(x) ≤ 0 over the interval [–1, ∞).
c. f(x) > 0 over the interval (–∞, 1).
d. f(x) < 0 over the interval (–∞. –1).

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.