9 terms

complementary angles

Two angles that add up to 90 degrees

vertical angles

A pair of opposite angles made when two lines cross. They will always be equal

adjacent angles

two angles that share the same vertex and have a common side

corresponding angles

two angles in the same location at two different intersections made by a transversal crossing parallel lines.

supplementary angles

two angles that add up to 180 degrees

interior angles of a triangle

Three angles that always add up to 180 degrees

straight angle

a straight line, which measures 180 degrees

transversal

a line that passes through two lines in the same plane at two distinct points

obtuse angle

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