Solve this equation: 2s + s + 12 = 132.
a. s = 9
b. s = –30
c. s = 120
d. s = 40

The equation given in the question is
2s + s + 12 = 132
3s + 12 = 132
3s = 132 - 12
3s = 120
s = 120/3
   = 40
From the above deduction we can see that the value of the unknown variable comes out to be exactly 40. This is possible because there is a single unknown variable and a single equation to get the value of the variable from. So the correct option among all the options given in the question is option "D".

If you would like to solve the equation 2 * s + s + 12 = 132, you can do this using the following steps:

2 * s + s + 12 = 132
3 * s = 132 - 12
3 * s = 120      /3
s = 120/3
s = 40

The correct result would be D. s = 40.