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adjacent angles

two angles in a plane that have a common vertex and a common side but no common interior points

alternate interior angles

the inside angles on opposite diagonal sides of a transversal crossing two parallel lines

alternate exterior angles

the outside angles on opposite diagonal sides of a transversal crossing two parallel lines

corresponding angles

the angles that lie in the same position or "match up" when a transversal crosses two parallel lines

line

a collection of points arranged in a straight path that extends without end in both directions

parallel lines

coplanar lines that never intersect

transversal

a line that intersects two or more lines in a plane