Question

How to prove two triangles congruent

Answer 1

There's a lot of theorems SAS, ASA, SSA, AAS, SSS

S=Side
A=Angle

If the order of the sides and angles in one of the above are congruent, then the triangles are congruent.

Hope this helps :D

Answer 2

To prove that two triangles are congruent, all three pairs of corresponding angles need to be congruent and the same. When two angles in one triangle are congruent to at least two angles in another triangle, the third angles are also congruent and therefor the triangles are congruent