Simplifying
15 + 5x = 0
Solving
15 + 5x = 0
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-15' to each side of the equation.
15 + -15 + 5x = 0 + -15
Combine like terms: 15 + -15 = 0
0 + 5x = 0 + -15
5x = 0 + -15
Combine like terms: 0 + -15 = -15
5x = -15
Divide each side by '5'.
x = -3
Simplifying
x = -3
