1. Proving Triangles Congruent
SSS, SAS, ASA, AAS, HL
Isosceles and Equilateral Triangles

2. Side-Side-Side (SSS) Congruence
If three sides of one triangle are congruent to three sides of a second triangle, then the triangles are congruent.

3. Side-Angle-Side (SAS) Congruence
If two sides and the included angle of one triangle are congruent to two sides and the included angle of a second triangle, then the triangles are congruent.

4. Angle-Side-Angle (ASA) Congruence
If two angles and the included side of one triangle are congruent to two angles and the included side of another triangle, then the triangles are congruent.

5. Angle-Angle-Side (AAS) Congruence
If two angles and the nonincluded side of one triangle are congruent to the corresponding two angles and side of a second triangle, then the two triangles are congruent.

6. Right Triangle Congruence

7. Isosceles Triangles
A triangle with at least two congruent sides.

8. Isosceles Triangle Theorem
If two sides of a triangle are congruent, then the angles opposite those sides are congruent.

9. Converse of Isosceles Triangle Theorem
If two angles of a triangle are congruent, then the sides opposite those angles are congruent.

10. Equilateral Triangles
A triangle is equilateral if and only if it is equiangular.
Each angle of an equilateral triangle measures 60.

11. Examples

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