(6+x)+x=42

Solution for (6+x)+x=42 equation:

Simplifying
(6 + x) + x = 42

Remove parenthesis around (6 + x)
6 + x + x = 42

Combine like terms: x + x = 2x
6 + 2x = 42

Solving
6 + 2x = 42

Solving for variable 'x'.

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

Add '-6' to each side of the equation.
6 + -6 + 2x = 42 + -6

Combine like terms: 6 + -6 = 0
0 + 2x = 42 + -6
2x = 42 + -6

Combine like terms: 42 + -6 = 36
2x = 36

Divide each side by '2'.
x = 18

Simplifying
x = 18