When two lines are crossed by another line (called the Transversal): The angles in matching corners are called Corresponding Angles.
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CPCTC is an acronym for the phrase 'corresponding parts of congruent triangles are congruent' It means that once we know that two triangles are congruent, we know that all corresponding sides and angles are congruent.
We use it to mean "sides" but the original meaning was "angles."
Complimentary angles are two or more angles that add up to 90 degrees
Supplementary angles are pairs of angles whose measures add up to 180 degrees.
Regular refers to a polygon of which all internal angles and side-lengths are equal.