6+3x=-2x+21

Solution for 6+3x=-2x+21 equation:

Simplifying
6 + 3x = -2x + 21

Reorder the terms:
6 + 3x = 21 + -2x

Solving
6 + 3x = 21 + -2x

Solving for variable 'x'.

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

Add '2x' to each side of the equation.
6 + 3x + 2x = 21 + -2x + 2x

Combine like terms: 3x + 2x = 5x
6 + 5x = 21 + -2x + 2x

Combine like terms: -2x + 2x = 0
6 + 5x = 21 + 0
6 + 5x = 21

Add '-6' to each side of the equation.
6 + -6 + 5x = 21 + -6

Combine like terms: 6 + -6 = 0
0 + 5x = 21 + -6
5x = 21 + -6

Combine like terms: 21 + -6 = 15
5x = 15

Divide each side by '5'.
x = 3

Simplifying
x = 3