State AA similarity criterion?

Hint: Here the given question is about the properties of similarities in two triangles, here we have to know that according to the given criterion when two angles, in a triangle are similar and corresponding angle pairs are congruent and all corresponding sides are proportional.

Complete step-by-step solution:
The given question is about to discuss about the AA criterion, here we have to understand the given property, let us take an example and then discuss the given criterion, on discussing we get:

Definition of AA triangle criterion: The AA criterion for triangle, similarity states that if two triangles have two pairs congruent angles, then the triangles are similar.
PROOF:
\[
   \Rightarrow In\,\Delta ABC\,and\,\Delta DEF \\
   \Rightarrow \angle CAB = \angle FDE\,and\,\angle ABC = \angle DEF \]
Hence from AA criteria the given two triangles are similar.

Note: The properties of triangles are predicted on the basis of congruency in which we decided according to the set of angles, which are common and the set of common sides. Here according to the both common side and angle we decide the congruency of the set of triangles.