Answer:
a: 120 = 2x + 40
80 = 2x
x = 40
b: (3x + 10) + (x-30) = 180
4x - 20 = 180
4x = 200
x = 50
c: 105 = 2x - 11
116 = 2x
58 = x
d: 8y + 36 = 14y - 24
-6y = -60
y = 10
64 = 48 + x
16 = x
y = 10, x = 16
e: 75 + (2x - 5) = 180
70 + 2x = 180
2x = 110
x = 55
2(55) - 5 =y
y = 105
f: (2x + 8) + (3x + 17) = 180
5x + 25 = 180
x = 31
3(31) + 17 = 5y + 15
110 = 5y + 15
95 = 5y
y = 19, x = 31