| A | B |
|---|
| Theorem 4-2 Third Angle Theorem | If two angles of one triangle are congruent to two angles of a second triangle, then the third angles of the triangles are congruent., |
| Theorem 4-1 Angle Sum Theorem | The sum of the measures of the angles of a triangle is 180., |
| Theorem 4-3 Exterior Angle Theorem | The measure of an exterior angle of a trianlge is equal to, |
| Corollary 4-1 | The acute angles of a right triangle are complementary., |
| Postulate 4-1 SSS | (Side - Side - Side) - If the sides of one triangle are congruent to the sides of a second triangle, then the triangles are congruent., |
| Postulate 4-2 SAS | Side - Included Angle - Side) - If two sides and the INCLUDED angle of one triangle are congruent to two sides and the INCLUDED angle of another triangle, then the triangles are congruent., |
| Postulate 4-3 ASA | (Angle - Included Side - Angle) - 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. |
| Postulate 4-3 AAS | (Angle - Angle - Side) - If two angles and a NON-INCLUDED side of one triangle are congruent to the corresponding two angles and side of a second triangle, the two triangles are congruent. |
| Theorem 4-6 Isosceles Triangle Theorem (ITT) | If two sides of a triangle are congruent, then the angles opposite those sides are congruent., |
| Theorem 4-7 Converse of the ITT | If two angles of a triangle are congruent, then the sides opposite those angles are congruent. |
| Corollary 4-3 | A triangle is equilateral if and only if it is equiangular. |
| Corollary 4-4 | Each angle of an equilateral triangle measures 60 degrees. |
