Adv. Geometry Unit 3 Proofs

Definition of Perpendicular Lines

Perpendicular lines form right angles
(biconditional statement)

If two lines are perpendicular

then they form congruent adjacent angles
(biconditional)

If two lines form congruent adjacent angles

then the lines are perpendicular
(biconditional)

Perpendicular Pair Theorem

If exterior sides of two adjacent angles are perpendicular then the angles are complementary.

Definition of Iscoeles Triangle

A triangle with two congruent sides is an isoceles triangle
(biconditional)

Definition of Right Triangle

A triangle with one right angle is a right triangle

If the angles are the angles of a triangle

then their sum is 180

If 2 angles of one triangle are congruent to 2 angles of another triangle

then the third angles are congruent

If 2 angles are the acute angles of a right triangle

then the angles are complementary

If the angle is the exterior angle of a triangle

then its measure equals the sum of the remote interior angles