Answer:
-12x + 4
Explanation:
(6x - 8 - 2x) - (12x - 7) - (4x - 5)
The subtraction sign before the parenthesis is basically multiplying by -1, so the subtraction signs in the parenthesis have to change to addition. After that, you can remove the parenthesis.
6x - 8 - 2x - 12x + 7 - 4x + 5
Simplified = -12x + 4