A triangle is one of the basic shapes of geometry. It is a polygon with 3 sides and 3 vertices/corners.
Two triangles are said to be congruent if their respective sides and angles are equal.
In order to prove that two triangles are congruent, it is sufficient to prove either of the following conditions:
Learnhive Lesson on Pythagoras Theorem
Learnhive Lesson on Congruence of Triangles