18x-x^2=86

Solution for 18x-x^2=86 equation:

Simplifying
18x + -1x2 = 86

Solving
18x + -1x2 = 86

Solving for variable 'x'.

Reorder the terms:
-86 + 18x + -1x2 = 86 + -86

Combine like terms: 86 + -86 = 0
-86 + 18x + -1x2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
86 + -18x + x2 = 0

Move the constant term to the right:

Add '-86' to each side of the equation.
86 + -18x + -86 + x2 = 0 + -86

Reorder the terms:
86 + -86 + -18x + x2 = 0 + -86

Combine like terms: 86 + -86 = 0
0 + -18x + x2 = 0 + -86
-18x + x2 = 0 + -86

Combine like terms: 0 + -86 = -86
-18x + x2 = -86

The x term is -18x.  Take half its coefficient (-9).
Square it (81) and add it to both sides.

Add '81' to each side of the equation.
-18x + 81 + x2 = -86 + 81

Reorder the terms:
81 + -18x + x2 = -86 + 81

Combine like terms: -86 + 81 = -5
81 + -18x + x2 = -5

Factor a perfect square on the left side:
(x + -9)(x + -9) = -5

Can't calculate square root of the right side.

The solution to this equation could not be determined.