Answers:
1. 65 + x = 90
x =25
2. 51 + x = 180
x =129
3. 107 + x = 180
x = 73
y = 107
z = 73
4. angle + 13 = 180 (supplementary means 180)
angle = 167
5. angle + 38 = 180 (supplementary means 90)
angle = 52
6. (5x + 9) + (3x +11) = 180
8x + 20 = 180
8x = 160
x = 20
angle 1 = 109 angle 2 = 71
7. 17x + 1 = 20x - 14
1 = 3x - 14
15 = 3x
5 = x
angle 1 = 86 angle 2 = 86
8. (3x + 3) + (10x - 4) = 90
13x -1 = 90
13x = 91
x = 7
angle 1 = 24 angle 2 = 66
9. p = 2q - 3; q + p = 180
p = 2(180 - p) - 3
p = 360 - 2p - 3
3p = 357
p = 119
______________
q + (119) = 90
q = 61
10. b = 3c + 2; b + c = 90
b = 3(90 - b) + 2
b = 270 - 3b + 2
4b = 272
p = 68
______________
c + (68) = 90
q = 22