Why are triangles congruent ?

Explanation:

Basically triangles are congruent when they have the same shape and size.

Two triangles are congruent if they have :

exactly the same three sides and

exactly the same three angles.

Tips Area :

If two sides and the included angle of one triangle are equal to the corresponding sides and angle of another triangle, the triangles are congruent too :)

If two angles and the included side of one triangle are equal to the corresponding angles and side of another triangle, the triangles are congruent too ;)

If two angles and the non-included side of one triangle are equal to the corresponding angles and side of another triangle, the triangles are congruent too ^^

Hope that help :)