Question 811923
3x + 18 = 2x - 2 
We want to use basic algebra operations to get x on the left by itself and the numerical values on the right
Subtract 18 from both sides and you have
3x + 18 - 18 = -2 - 18
3x = 2x - 20
subtract 2x from both sides
3x - 2x = 2x - 2x - 12
which is
x = -20