Complementary, Supplementary, Vertical Angles
Supplementary Angles
ACD and BCD are adjacent angles that are supplementary. These angle pairs are sometimes called Linear Pair Angles or Straight Angles because they form a straight line. Notice that even when you move point D, the angles still add to 180.
Complementary Angles
JKM and LKM are adjacent angles that are complementary. Notice that even when you move point M, the angles still add to 90.
Vertical Angles
GIE and HIF, shown in blue, are a pair of Vertical Angles. GIF and HIE, shown in green, are also a pair of Vertical Angles. Notice that the vertical angles are the angles opposite of each other. Also notice that the vertical angles are congruent (the same). Look at one blue angle and one green angle. What do you notice about their relationship?
Which angle pairs are congruent (equal)?