87-15=x

Solution for 87-15=x equation:

Simplifying
87 + -15 = x

Combine like terms: 87 + -15 = 72
72 = x

Solving
72 = 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.
72 + -1x = x + -1x

Combine like terms: x + -1x = 0
72 + -1x = 0

Add '-72' to each side of the equation.
72 + -72 + -1x = 0 + -72

Combine like terms: 72 + -72 = 0
0 + -1x = 0 + -72
-1x = 0 + -72

Combine like terms: 0 + -72 = -72
-1x = -72

Divide each side by '-1'.
x = 72

Simplifying
x = 72