Answer:
Simplifying
-9x + 4 + -12 = 64
Reorder the terms:
4 + -12 + -9x = 64
Combine like terms: 4 + -12 = -8
-8 + -9x = 64
Solving
-8 + -9x = 64
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '8' to each side of the equation.
-8 + 8 + -9x = 64 + 8
Combine like terms: -8 + 8 = 0
0 + -9x = 64 + 8
-9x = 64 + 8
Combine like terms: 64 + 8 = 72
-9x = 72
Divide each side by '-9'.
x = -8
Simplifying
x = -8