x+3+6+x=0

Solution for x+3+6+x=0 equation:

Simplifying
x + 3 + 6 + x = 0

Reorder the terms:
3 + 6 + x + x = 0

Combine like terms: 3 + 6 = 9
9 + x + x = 0

Combine like terms: x + x = 2x
9 + 2x = 0

Solving
9 + 2x = 0

Solving for variable 'x'.

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

Add '-9' to each side of the equation.
9 + -9 + 2x = 0 + -9

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

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

Divide each side by '2'.
x = -4.5

Simplifying
x = -4.5