We are asked to name the postulate we would use to prove that the given triangles are congruent. To do so, we will start by labeling the vertices in the given diagram.
In the diagram, we can see that BC ≅ DC, AC ≅ CE, and ∠ACB ≅ ∠DCE. Therefore, two pairs of corresponding sides and their included angles are congruent. This means that △ABC ≅ △DCE by the Side-Angle-Side Congruence Postulate (SAS).
