-(x-7)(x-1)=15

Solution for -(x-7)(x-1)=15 equation:

Simplifying
-1(x + -7)(x + -1) = 15

Reorder the terms:
-1(-7 + x)(x + -1) = 15

Reorder the terms:
-1(-7 + x)(-1 + x) = 15

Multiply (-7 + x) * (-1 + x)
-1(-7(-1 + x) + x(-1 + x)) = 15
-1((-1 * -7 + x * -7) + x(-1 + x)) = 15
-1((7 + -7x) + x(-1 + x)) = 15
-1(7 + -7x + (-1 * x + x * x)) = 15
-1(7 + -7x + (-1x + x2)) = 15

Combine like terms: -7x + -1x = -8x
-1(7 + -8x + x2) = 15
(7 * -1 + -8x * -1 + x2 * -1) = 15
(-7 + 8x + -1x2) = 15

Solving
-7 + 8x + -1x2 = 15

Solving for variable 'x'.

Reorder the terms:
-7 + -15 + 8x + -1x2 = 15 + -15

Combine like terms: -7 + -15 = -22
-22 + 8x + -1x2 = 15 + -15

Combine like terms: 15 + -15 = 0
-22 + 8x + -1x2 = 0

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

Divide each side by '-1'.
22 + -8x + x2 = 0

Move the constant term to the right:

Add '-22' to each side of the equation.
22 + -8x + -22 + x2 = 0 + -22

Reorder the terms:
22 + -22 + -8x + x2 = 0 + -22

Combine like terms: 22 + -22 = 0
0 + -8x + x2 = 0 + -22
-8x + x2 = 0 + -22

Combine like terms: 0 + -22 = -22
-8x + x2 = -22

The x term is -8x.  Take half its coefficient (-4).
Square it (16) and add it to both sides.

Add '16' to each side of the equation.
-8x + 16 + x2 = -22 + 16

Reorder the terms:
16 + -8x + x2 = -22 + 16

Combine like terms: -22 + 16 = -6
16 + -8x + x2 = -6

Factor a perfect square on the left side:
(x + -4)(x + -4) = -6

Can't calculate square root of the right side.

The solution to this equation could not be determined.