A linear pair is a pair of adjacent angles formed when two lines intersect. The angles in a linear pair are supplementary, meaning their measures add up to 180 degrees. For example, if one angle measures 70 degrees, the other in the pair must measure 110 degrees to complete the total of 180 degrees. In a linear pair, the two angles share a common vertex and a common side, while the other sides extend in opposite directions. This concept is important in geometry, particularly in the study of angles and intersecting lines. Understanding linear pairs helps in solving various geometric problems.