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.
(5 + -1x)(17 + x) = 0

Subproblem 1
Set the factor '(5 + -1x)' equal to zero and attempt to solve:

Simplifying
5 + -1x = 0

Solving
5 + -1x = 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 + -1x = 0 + -5

Combine like terms: 5 + -5 = 0
0 + -1x = 0 + -5
-1x = 0 + -5

Combine like terms: 0 + -5 = -5
-1x = -5

Divide each side by '-1'.
x = 5

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

Simplifying
17 + x = 0

Solving
17 + x = 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 + x = 0 + -17

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

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

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