Answer:
ASA congruence postulate
Explanation:
The ASA (Angle-Side-Angle) congruence postulate states that if two triangles have two angles and the included side (the side between the vertices of the two angles) congruent, then the triangles are congruent.
The two congruent angles are ∠ACB ≅ ∠CAD and ∠CAB ≅ ∠DCA. The included side is segment AC