85=x(x-12)

Solution for 85=x(x-12) equation:

Simplifying
85 = x(x + -12)

Reorder the terms:
85 = x(-12 + x)
85 = (-12 * x + x * x)
85 = (-12x + x2)

Solving
85 = -12x + x2

Solving for variable 'x'.

Reorder the terms:
85 + 12x + -1x2 = -12x + 12x + x2 + -1x2

Combine like terms: -12x + 12x = 0
85 + 12x + -1x2 = 0 + x2 + -1x2
85 + 12x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
85 + 12x + -1x2 = 0

Factor a trinomial.
(17 + -1x)(5 + x) = 0

Subproblem 1
Set the factor '(17 + -1x)' equal to zero and attempt to solve:

Simplifying
17 + -1x = 0

Solving
17 + -1x = 0

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

Add '-17' to each side of the equation.
17 + -17 + -1x = 0 + -17

Combine like terms: 17 + -17 = 0
0 + -1x = 0 + -17
-1x = 0 + -17

Combine like terms: 0 + -17 = -17
-1x = -17

Divide each side by '-1'.
x = 17

Simplifying
x = 17
Subproblem 2
Set the factor '(5 + x)' equal to zero and attempt to solve:

Simplifying
5 + x = 0

Solving
5 + x = 0

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

Add '-5' to each side of the equation.
5 + -5 + x = 0 + -5

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

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

Simplifying
x = -5
Solution
x = {17, -5}