# Lines cut by a Transversal, IF parallel ... Then ...

VERTICAL ANGLES

Two non-adjacent angles that are formed by intersecting lines. They make a bow tie and they are congruent.

LINEAR PAIR

A pair of adjacent angles that make a straight angle. These angles are supplementary.

ALTERNATE INTERIOR ANGLES

Angles that are in between two lines but on opposite sides of a transversal. If the lines are parallel then these angles are congruent.

SAME SIDE INTERIOR ANGLES

These angles are on the same side of the transversal and they are in between two parallel lines. These angles are supplementary.

ALTERNATE EXTERIOR ANGLES

Angles that are outside of the parallel lines but they are on the opposite side of the transversal. This pair of angle are congruent.

CORRESPONDING ANGLES

Angles that occupy the same spots on the transversal and the parallel lines. These angles are congruent.

TRANSVERSAL

A line that intersects two or more coplanar lines at different points, (line t above).

PARALLEL LINES

Coplanar lines that do not intersect.

PERPENDICULAR LINES

Two lines that intersect to form right angles

SKEW LINES

Lines on different planes that do not not intersect.

PARALLEL PLANES

Two planes that do not intersect