Name ______________________________________________________
PreAlgebra
Date _______________________
Notes 9.2 Angle Relationships
Def: Adjacent angles share a vertex and a side but have no common interior points.
Def: Vertical angles are formed by two intersecting lines and are opposite each other. Vertical angles are congruent.
Def: Congruent angles are angles that have the same measure.
Def: Supplementary angles are angles whose measures sum to 180 .
Def: Complementary angles are angles whose measures sum to 90 .
Def: A transversal is a line that intersects two other lines in different points. Some pairs of angles formed by transversals have
special names.
Def: Corresponding angles lie on the same side of the transversal in corresponding positions. Corresponding angles formed by
a transversal that cuts through parallel lines are congruent.
1 and 3 are corresponding
2 and 4 are corresponding
8 and 6 are corresponding
7 and 5 are corresponding
Def: Alternate interior angles are in the interior of the pair of lines and are on opposite sides of the transversal. Alternate
interior angles formed by a transversal that cuts through parallel lines are congruent.
2 and 6 are alternate interior
7 and 3 are alternate interior
Def: Alternate exterior angles are on the exterior of the pair of lines and are on opposite sides of the transversal. Alternate
exterior angles formed by a transversal that cuts through parallel lines are congruent.
1 and 5 are alternate exterior
8 and 4 are alternate exterior
Def: Same side interior angles are in the interior of the pair of lines and are on the same side of the transversal. Same side
interior angles formed by a transversal that cuts through parallel lines are supplementary.
2 and 3 are same side interior
7 and 6 are same side interior
Def: Same side exterior angles are on the exterior of the pair of lines and are on the same side of the transversal. Same side
exterior angles formed by a transversal that cuts through parallel lines are supplementary.
1 and 4 are same side exterior
8 and 5 are same side exterior