-15-6=x+6-6

Solution for -15-6=x+6-6 equation:

Simplifying
-15 + -6 = x + 6 + -6

Combine like terms: -15 + -6 = -21
-21 = x + 6 + -6

Reorder the terms:
-21 = 6 + -6 + x

Combine like terms: 6 + -6 = 0
-21 = 0 + x
-21 = x

Solving
-21 = x

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-1x' to each side of the equation.
-21 + -1x = x + -1x

Combine like terms: x + -1x = 0
-21 + -1x = 0

Add '21' to each side of the equation.
-21 + 21 + -1x = 0 + 21

Combine like terms: -21 + 21 = 0
0 + -1x = 0 + 21
-1x = 0 + 21

Combine like terms: 0 + 21 = 21
-1x = 21

Divide each side by '-1'.
x = -21

Simplifying
x = -21