Answer: -3
Explanation:
First... Distribute the -3 into x and -8. You'll have -3x + 24 + 7x = 12
Next... Subtract 24 on both sides (-3x + 24 - 24 + 7x = 12 - 24)
-3x + 7x = -12
Add like terms to get 4x = -12
Finally.. you divide 4 on both and you have...
x = -3