x+(3+n)+(6+n)=57

Solution for x+(3+n)+(6+n)=57 equation:

Simplifying
x + (3 + n) + (6 + n) = 57

Remove parenthesis around (3 + n)
x + 3 + n + (6 + n) = 57

Remove parenthesis around (6 + n)
x + 3 + n + 6 + n = 57

Reorder the terms:
3 + 6 + n + n + x = 57

Combine like terms: 3 + 6 = 9
9 + n + n + x = 57

Combine like terms: n + n = 2n
9 + 2n + x = 57

Solving
9 + 2n + x = 57

Solving for variable 'n'.

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

Add '-9' to each side of the equation.
9 + 2n + -9 + x = 57 + -9

Reorder the terms:
9 + -9 + 2n + x = 57 + -9

Combine like terms: 9 + -9 = 0
0 + 2n + x = 57 + -9
2n + x = 57 + -9

Combine like terms: 57 + -9 = 48
2n + x = 48

Add '-1x' to each side of the equation.
2n + x + -1x = 48 + -1x

Combine like terms: x + -1x = 0
2n + 0 = 48 + -1x
2n = 48 + -1x

Divide each side by '2'.
n = 24 + -0.5x

Simplifying
n = 24 + -0.5x