Angle Relationships

Angle

two rays with a common endpoint

Vertex

common endpoint of an angle

Acute angles

angles that are less than 90 degrees

Right angle

an angle that measures exactly 90 degrees

Obtuse Angle

An angle that measures more than 90 degrees but less than 180 degrees

Straight Angle

an angle that measures exactly 180 degrees

Congruent Angles

angles that have the same measure

Supplementary Angles

Two angles whose sum is 180 degrees

Complimentary Angles

Two angles whose sum is 90 degrees

Transversal

a line that intersects two or more parallel lines

corresponding angles

angles in the same place on different lines

Alternate exterior angles

Angles that lay outside the parallel lines and are on opposite sides of the transversal; They are congruent.

Alternate interior angles

Angles that lay inside the parallel lines and are on opposite sides of the transversal; They are congruent.