9+12x=42+x

Solution for 9+12x=42+x equation:

Simplifying
9 + 12x = 42 + x

Solving
9 + 12x = 42 + 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.
9 + 12x + -1x = 42 + x + -1x

Combine like terms: 12x + -1x = 11x
9 + 11x = 42 + x + -1x

Combine like terms: x + -1x = 0
9 + 11x = 42 + 0
9 + 11x = 42

Add '-9' to each side of the equation.
9 + -9 + 11x = 42 + -9

Combine like terms: 9 + -9 = 0
0 + 11x = 42 + -9
11x = 42 + -9

Combine like terms: 42 + -9 = 33
11x = 33

Divide each side by '11'.
x = 3

Simplifying
x = 3