Corresponding Angles
The term corresponding angles is often used when two lines are cut by a third line, a transversal .
In the figure above, line is a transversal cutting lines and , and there are four pairs of corresponding angles:
and
and
and
and
The Corresponding Angles Postulate states that if and are parallel , then the pairs of corresponding angles are congruent . The converse of this theorem is also true.
The term corresponding angles is also sometimes used when making statements about similar or congruent polygons . For example, in the figure below featuring two similar pentagons, and are corresponding angles.