Use the figure for Exercises 13-15. Find the measure of the given angle.
112°
430
33°
1710
b
15. C
13. a
14. b

Answer:
a + 112 + 33 = 180 ( sum of interior angles of tria
or a + 145 = 180 - ngle is 180 degrees)
or a = 180 - 145
or a = 35 .
similarily,
c + 43 + 71 = 180
or c + 114 = 180
or c = 180 - 114
or c = 66 .
and ,
a + 71 + b = 180 ( sum of angles in straight line is or, 35 +71 + b = 180 180 degrees)
or , b + 106 = 180
or, b = 180 - 106
or, b = 74 .
Thank me later.