Name Date Class LESSON Reading Strategies 12-5 Use a Graphic Aid The graphic aid below summarizes angle relationships in circles. Angle Relationships in Circles Vertex lies Vertex lies Vertex lies on a circle. inside a circle. outside a circle. Angle measure Angle measure is Angle measure is half the difference of half the measure is half the sum of the measures of the of the intercepted the measures of the intercepted arcs. arc. intercepted arcs. 65 60 30 mZXYZ = - (650) mZAEB = MZDEC mZACB = (76 -30) 2 - (840 + 60 0 ) = 720 2 = 32.5 = 23 Find each measure. 1. mZRZS WY 2. mZHIJ 320 120c G 130c 3. mZXVQ 4. mZACB 240 1020 Original content Copyright @ by Holt Mcdougal. Additions and changes to the original content are the responsibility of the instructor. 12-42 Holt Mcdougal Geometry