Question | Answer |
Triangle Sum Theorem | the sum of the measures of the interior angles of a triangle is 180 degrees |
Exterior Angle Theorem | The measure of an exterior angle of a triangle is equal to the sum of the measures of the two nonadjacent interior angles |
Corollary to triangle sum theorem | The acute angles of a right triangle are complementary |
Third Angle Theorem | If two angles of one triangle are congruent to two angles of another triangle, then the third angles are congruent. |
Base Angles Theorem | If two sides of a triangle are congruent, then the angles opposite them are congruent |
Converse of the Base Angles Theorem | If two angles of a triangle are congruent, then the sides opposite them are congruent. |
Side-Side-Side Congruence Postulate (SSS) | If three sides of one triangle are congruent to three sides of a second triangle, then the two triangles are congruent |
Side-Angle-Side Congruence Postulate (SAS) | 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 two triangles are congruent |
Hypotenuse-Leg (HL) Congruence Theorem | If the hypotenuse and a leg of a triangle are congruent to the hypotenuse and a leg of a second triangle, then the two triangles are congruent. |
Angle-Side-Angle Congruence Postulate (ASA) | If two angles and the included side of one triangle are congruent to two angles and the included side of a second triangle, then the two triangles are congruent |
Angle-Angle-Side Congruence Postulate (AAS) | If two angles and a nonincluded side of one triangle are congruent to two angles and a nonincluded side of a second triangle, then the two triangles are congruent |