Answer:
Explanation:
1.Distribute
12x - 66 + 15 =21
2.Add the numbers
12x-51=21
3.Add 51 to both sides of the equation
12x -51 +51 = 21+51
4.Simplify
12x=72
5. Divide both sides of the equation by the same term
12x/12 = 72/12
6. Divide the numbers
x=6
And you have your answer x=6