Final answer:
When two lines intersect, they create four linear pairs of angles which are adjacent and their non-common sides form a straight line.
Step-by-step explanation:
When two lines intersect, they form four linear pairs of angles. A linear pair is a set of two adjacent angles whose non-common sides form a straight line, or in other words, the sum of their measures is equal to 180 degrees. For instance, if you have two intersecting lines creating angles A, B, C, and D at the intersection, then the linear pairs would be (A,B), (B,C), (C,D), and (D,A).
Learn more about Linear Pairs of Angles