
Congruent Complements Theorem
If two angles are complementary to the same angle or to congruent angles, then they are congruent. (page 91)
Vertical Angles Theorem
If two angles are vertical angles, then they are congruent. (page 92)
Transitive Property of Parallel Lines
If two lines are parallel to the same line, then they are parallel to each other. (page 105)
Property of Perpendicular Lines
If two coplanar lines are perpendicular to the same line, then they are parallel to each other. (page 106)
Alternate Interior Angles Theorem
If two parallel lines are cut by a transvesal, then the pairs of alternate interior angles are congruent. (page 135)
Consecutive Interior Angles Theorem
If two parallel lines are cut by a transversal, then the pairs of consecutive interior angles are supplementary. (page 135)
Alternate Exterior Angles Theorem
If two parallel lines are cut by a transversal, then the pairs of alternate exterior angles are congruent. (page 135)
Perpendicular Tranversal Theorem
If a tranversal is perpendicular to one of two paralell lines, then it is perpendicular to the second. (page 135)
Alternate Interior Angles Converse
If Two lines are cut by a transversal so that alternate interior angles are congruent, then the lines are parallel. (page 141)
Consecutive Interior Angles Converse
If two lines are cut by a transversal so that consecutive interior angles are supplementary, then the lines are parallel. (page 141)
Alternate Exterior Angles Converse
If two lines are cut by a transversal so that alternate exterior angles are congruent, then the lines are parallel. (page 141)
