What are congruence theorems and postulates?

Answer 1

If the sides AB, BC and CA of triangle ABC correspond to the sides DE, EF and FD of triangle DEF, then the two triangles are congruent if:

• AB = DE, BC = EF and CA = FD (SSS)
• AB = DE, BC = EF and angle ABC = angle DEF (SAS)
• AB = DE, angle ABC = angle DEF, angle BCA = angle EFD (ASA)

If the triangles are right angled at A and D so that BC and EF are hypotenuses, then the triangles are congruent if

• BC = EF and AB = DE (RHS)
• BC = EF and angle ABC = angle DEF (RHA).