The purpose of this exercise is to have students identify whether a given pair of angles created by parallel lines crossed by a transversal are congruent or supplementary. As an extension, have students defend their answers using the basic postulates and theorems: Linear Pair Postulate (LP), Vertical Angle Theorem (VA), Corresponding Angles Postulate (CA), Alternate Interior Angle Theorem (AIA), Alternate Exterior Angle Theorem (AEA), and Consecutive Angle Theorem (CA). Notice that some diagram will require two postulates or theorems.