Sec. 1.5: Angle Pairs There are five special pairs of angles: 1.Adjacent angles 2.Complementary Angles 3.Supplementary Angles 4.Vertical Angles 5.A Linear Pair
Adjacent Angles Two angles are adjacent if they share a common vertex and side, but have no common interior points.
Complementary Angles Two angles are complementary if their angle measures add up to 90 degrees. Assuming the measures of angle 3 and 4 above add up to 90 degrees.
Supplementary Angles Two angles are supplementary if their angle measures add up to 180 degrees. Assuming the measures of angle 7 and 8 above add up to 180 degrees.
Vertical Angles Vertical angles are any pair of non-adjacent angles formed by two intersecting lines.
A Linear Pair A linear pair of angles are adjacent angles whose non-common sides are opposite rays.