Geometry · Triangles & Congruence
ASA Congruence
HSG-SRT.B.5
Definition
Triangles are congruent if two angles and the side between them are equal.
Examples
- Two angles and the included side matching proves triangles congruent by ASA.
- Triangles with 40 and 60 degree angles and a matching included side are congruent by ASA.
Key rule
The side in ASA must be the included side — the one between the two given angles.
Memory hook
Angle, Side, Angle — the side must be sandwiched between the angles.