Prove Theorems Advanced Geometry Deductive Reasoning Lesson 4

Definition of right angle Reasons Definition of straight angle Definition of linear pair Definition of perpendicular lines **Once you have proven a theorem, it can be used in any later proof as a reason.

Midpoint Theorem If M is the midpoint of, then A B M

Supplement Theorem If two angles form a linear pair, then they are supplementary angles.

Angles complementary to the same angle or to congruent angles are congruent

Vertical Angles Theorem If two angles are vertical angles, then they are congruent

If two angles are congruent and supplementary, then each angle is a right angle.