### Concept (1)

If two triangles are congruent, all three corresponding sides are congruent and all three corresponding angles are congruent. If two pairs of corresponding angles and the side between them are known to be congruent, the triangles are congruent. This shortcut is known as angle-side-angle (ASA). Another shortcut is angle-angle-side (AAS), where two pairs of angles and the non-included side are known to be congruent. ASA and AAS are important when solving proofs.

### Sample Problems (4)

Need help with "ASA and AAS" problems? Watch expert teachers solve similar problems to develop your skills. ###### Problem 1
How to use ASA and AAS and vertical angles to determine congruence of triangles and denote the congruence correctly. ###### Problem 2
How to use ASA and AAS and properties of angles formed by a transversal of parallel lines to determine the congruence of vertical triangles and denote the congruence correctly. ###### Problem 3
How to use ASA and AAS to determine if two adjacent triangles are congruent, or how to determine if there is not enough information to prove congruence. ###### Problem 4
How to use ASA and AAS to determine the congruence of adjacent triangles and denote the congruence correctly.