How to know a triangle is congruent

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

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.