(5+-y)+(6+-y)+-(5+-y)=0

Solution for (5+-y)+(6+-y)+-(5+-y)=0 equation:

Simplifying
(5 + -1y) + (6 + -1y) + -1(5 + -1y) = 0

Remove parenthesis around (5 + -1y)
5 + -1y + (6 + -1y) + -1(5 + -1y) = 0

Remove parenthesis around (6 + -1y)
5 + -1y + 6 + -1y + -1(5 + -1y) = 0
5 + -1y + 6 + -1y + (5 * -1 + -1y * -1) = 0
5 + -1y + 6 + -1y + (-5 + 1y) = 0

Reorder the terms:
5 + 6 + -5 + -1y + -1y + 1y = 0

Combine like terms: 5 + 6 = 11
11 + -5 + -1y + -1y + 1y = 0

Combine like terms: 11 + -5 = 6
6 + -1y + -1y + 1y = 0

Combine like terms: -1y + -1y = -2y
6 + -2y + 1y = 0

Combine like terms: -2y + 1y = -1y
6 + -1y = 0

Solving
6 + -1y = 0

Solving for variable 'y'.

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

Add '-6' to each side of the equation.
6 + -6 + -1y = 0 + -6

Combine like terms: 6 + -6 = 0
0 + -1y = 0 + -6
-1y = 0 + -6

Combine like terms: 0 + -6 = -6
-1y = -6

Divide each side by '-1'.
y = 6

Simplifying
y = 6