x-1-(x-2)(x+2)=9

Solution for x-1-(x-2)(x+2)=9 equation:

Simplifying
x + -1 + -1(x + -2)(x + 2) = 9

Reorder the terms:
x + -1 + -1(-2 + x)(x + 2) = 9

Reorder the terms:
x + -1 + -1(-2 + x)(2 + x) = 9

Multiply (-2 + x) * (2 + x)
x + -1 + -1(-2(2 + x) + x(2 + x)) = 9
x + -1 + -1((2 * -2 + x * -2) + x(2 + x)) = 9
x + -1 + -1((-4 + -2x) + x(2 + x)) = 9
x + -1 + -1(-4 + -2x + (2 * x + x * x)) = 9
x + -1 + -1(-4 + -2x + (2x + x2)) = 9

Combine like terms: -2x + 2x = 0
x + -1 + -1(-4 + 0 + x2) = 9
x + -1 + -1(-4 + x2) = 9
x + -1 + (-4 * -1 + x2 * -1) = 9
x + -1 + (4 + -1x2) = 9

Reorder the terms:
-1 + 4 + x + -1x2 = 9

Combine like terms: -1 + 4 = 3
3 + x + -1x2 = 9

Solving
3 + x + -1x2 = 9

Solving for variable 'x'.

Reorder the terms:
3 + -9 + x + -1x2 = 9 + -9

Combine like terms: 3 + -9 = -6
-6 + x + -1x2 = 9 + -9

Combine like terms: 9 + -9 = 0
-6 + x + -1x2 = 0

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

Divide each side by '-1'.
6 + -1x + x2 = 0

Move the constant term to the right:

Add '-6' to each side of the equation.
6 + -1x + -6 + x2 = 0 + -6

Reorder the terms:
6 + -6 + -1x + x2 = 0 + -6

Combine like terms: 6 + -6 = 0
0 + -1x + x2 = 0 + -6
-1x + x2 = 0 + -6

Combine like terms: 0 + -6 = -6
-1x + x2 = -6

The x term is x.  Take half its coefficient (0.5).
Square it (0.25) and add it to both sides.

Add '0.25' to each side of the equation.
-1x + 0.25 + x2 = -6 + 0.25

Reorder the terms:
0.25 + -1x + x2 = -6 + 0.25

Combine like terms: -6 + 0.25 = -5.75
0.25 + -1x + x2 = -5.75

Factor a perfect square on the left side:
(x + 0.5)(x + 0.5) = -5.75

Can't calculate square root of the right side.

The solution to this equation could not be determined.