Download Parallel and Perpendicular Lines

Parallel and Perpendicular Lines
Proofs and Statements
Mr. Durkin
WAYS TO PROVE LINES ARE PERPENDICULAR:
1. If two intersecting lines form congruent adjacent angles, the lines
are perpendicular.
2. When two lines or segments form right angles, they are
perpendicular.
3. When 2 points on one line or segment, each of which is equidistant
From the endpoints of the other line segment, they are
perpendicular to each other.
WAYS TO PROVE LINES ARE PARALLEL:
1. If 2 lines are each parallel to a third line, they are parallel to
Each other.
2. When 2 lines are cut by a transversal and a pair of alternate
Interior angles are congruent, the lines are parallel.
3. When 2 lines are cut by a transversal and a pair of Corresponding
angles are congruent, the lines are parallel.
4. When 2 lines are cut by a transversal and a pair of
Interior angles on the same side of the transversal are
supplementary, the lines are parallel.
PROVING RIGHT TRIANGLES BY HYPOTENUSE/LEG:
A Right Triangle is congruent to another Right Triangle if the
Hypotenuse and one leg of each triangle are congruent.
THE SUM OF INTERIOR ANGLES OF ANY POLYGON:
The sum of the interior angles of any polygon = 180(n-2),
Where n is the number of sides in the polygon.