Subtract 3 from both sides.
6|x - 2| = 36
Divide both sides by 6 to get the absolute value by itself.
|x - 2| = 6
Absolute value will turn negative numbers into a positive. Therefore, you can use the following equations to find the values of x that will fit this equation:
x - 2 = 6
x - 2 = -6
Add 2 to both sides to get x by itself.
x = -4
x = 8
The values of x where f(x) = 39 are x = -4, and x = 8.