Question

which postulate or theorem proves that △ cfe and △ dfe are congruent? sas congruence postulate asa congruence postulate sss congruence postulate aas congruence theorem

Explanation:

From the diagram: 1) $CF = DF$ (marked with double lines), 2) $CE = DE$ (marked with single lines), 3) $FE = FE$ (common side). All three pairs of corresponding sides are equal, so $\triangle CFE \cong \triangle DFE$ by SSS.

Answer:

SSS Congruence Postulate