<p>Notes: Special Pairs of Angles</p><p>Congruent Angles: Angles of equal measure.</p><p>Vertical Angles: Angles opposite each other when 2 lines intersect. Vertical angles are congruent. a b d c m a = m c m b = m d (“measure of angle b equals the measure of angle d”)</p><p>Bisector: Cuts an angle into 2 equal parts.</p><p>45˚ 45˚ Bisector</p><p>Adjacent angles: Angles that have the same vertex and share a side but do not overlap.</p><p>● D C● ● B</p><p>A●  CAB is adjacent to  DAC</p><p>Complementary Angles: 2 angles whose sum is 90 degrees. Example: A 40˚ degree angle and a 50˚ angle are complementary. (They do not need to be adjacent) </p><p>Supplementary Angles: 2 angles whose sum is 180 degrees. Example: A 160˚ angle and a 20˚ angle are supplementary. (Do not need to be adjacent) Practice with Special Angle Pairs Use this diagram for questions 1,2,3:</p><p>B C </p><p>A D</p><p>1) How many degrees are in angle ABC? ______</p><p>2) How many degrees are in angle ABD if angle DBC is 15°? ______</p><p>3) Angle ABD and Angle DBC are called ______angles.</p><p>Use this diagram for questions 4-7: 1 4 2 3</p><p>4) What is the relationship between angles 1 and 2? ______and </p><p> they are also ______</p><p>5) What is the relationship between angles 1 and 4? ______and </p><p> they are also ______</p><p>6) What is true about angles 2 and 4? ______</p><p>7) If angle 1 measures 125 degrees:</p><p>Find m 2 ______</p><p>Find m 3 ______</p><p>Find m 4 ______</p>