How to know a triangle is congruent

The answer is SAS (side, angle, side) SAS stands for "side, angle, side" and means that we have two triangles where we know two sides and the included angle are equal. If two sides and the included angle of one triangle are equal to the corresponding sides and angle of another triangle, thetriangles are congruent.

By the degree of the angles if they are the same degree or position.

Iwould say they are complementary because that’s the division of a 90 degree angle and it’s split between the middle of them