6+4x=x+21

Solution for 6+4x=x+21 equation:

Simplifying
6 + 4x = x + 21

Reorder the terms:
6 + 4x = 21 + x

Solving
6 + 4x = 21 + 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.
6 + 4x + -1x = 21 + x + -1x

Combine like terms: 4x + -1x = 3x
6 + 3x = 21 + x + -1x

Combine like terms: x + -1x = 0
6 + 3x = 21 + 0
6 + 3x = 21

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

Combine like terms: 6 + -6 = 0
0 + 3x = 21 + -6
3x = 21 + -6

Combine like terms: 21 + -6 = 15
3x = 15

Divide each side by '3'.
x = 5

Simplifying
x = 5