Congruent Triangles

SSS,SAS

Shapes are congruent if they have exactly the same length sides and the same internal angles.

The best way to make sure triangles are congruent is to re-draw them in the same direction and check to see if they have these features:

SSS

Have all three sides the same. It doesn’t matter if the side has been reflected or rotated, if the lengths are the same, the angles will be the same and the triangles will therefore be congruent.

Side-Side-Side

3 same sides = congruent

SAS

In this case the known angle is between two known sides.

Side-Angle-Side

ASARHS

ASA

Angle-Side-Angle

RHS

Right Angle-Hypotenuse-Side

For right angle triangles, you just need to check the hypotenuse and one other side is the same.