Name: _______________________________ 1.5: Angle Relationships Pair-Share: Use the diagram below and a protractor to measure each angle. Answer the follow-up questions! Find the measure of each angle: 1) m<MKS = __________ 2) m<MKJ = __________ 3) m<JKA = __________ 4) m<SKA = __________ 5) Write your angle measurements into each angle in the diagram. What pattern do you notice? 6) Compare <JKA and <SKA. How are these angles related to each other both in position and in measurement? 7) Compare <MKS and <JKA. How are these angles related to each other both in position and in measurement? 8) Do you think these angle relationships are always true for two intersecting lines? Why or why not? Vocab Definition Diagram Adjacent angles Two angles in the same plane with a common vertex and side, but have no common interior points. Linear pair 1 2 A pair of adjacent angles whose non common sides are opposite rays. 2 1 Two angle whose measures have a sum of _______. Complementary (the angles are not always adjacent) angles 1 2 Two angle whose measures have a sum of _______. Supplementary angles 1 (the angles are not always adjacent) Two nonadjacent angles formed by two Vertical angles __________________________ lines. 1 These angles are always 2 ____________________. Perpendicular Lines Intersecting lines that form __________ angles. 2 Practice: 1) DEF and both angles. FEG are complementary. m DEF = 3x – 4 and m FEG = 5x+6. Find the measure of Step 1: Define key word Step 2: Draw a picture Step 3: Write an equation! 2) <ABC and <GHI are supplementary angles. m<ABC = 8x – 2 and m<GHI = x + 20. Find the measure of both angles. 3) Find the measure of 2 supplementary angles if the difference in the measures of the two angles is 18. (Hint: Set one of the angles equal to “x”- our unknown) 4) Find x. Remember, what kind of angles are these? x (5x-48) 5) Find x and y so that KO and HM are perpendicular. 1.1-1.4 Review 6) Find the distance between points A(-2, 5) and B(3, 4). 7) Find the midpoint of EF with endpoints E(6, 8) and F(-1, -5). 8) Find the coordinates of T if M(2, -5) is the midpoint of TW with W(-6, 1). 9) In the figure, and are opposite rays, bisects ∠EBC. a) If m∠ EBD = 4x + 16 and m∠ DBC = 6x + 4, find m∠ EBD. b) If m∠ EBD = 4x - 8 and m∠ EBC = 5x + 20, find the value of x and m∠ EBC. Homework: p.51-52 #8, 14, 16, 19-25 odd, 29