Answer:
First state that two triangles are similar if their corresponding angles are congruent and the corresponding sides are in proportion.
Let's take two triangles that are similar:
Taking two triangles:
[tex]{\triangle ABC \text{ and } \triangle PQR[/tex]
If
[tex]\angle A \displaystyle \cong \angle P[/tex]
and
[tex]\angle C \displaystyle \cong \angle R[/tex]
Then,
[tex]{\triangle ABC \sim \triangle PQR[/tex]
It is Angle-Angle (or AA) Theorem.
It says that two triangles are similar if they have two pairs of corresponding angles that are congruent.
