-x^2+8x+16=28

Solution for -x^2+8x+16=28 equation:

Simplifying
-1x2 + 8x + 16 = 28

Reorder the terms:
16 + 8x + -1x2 = 28

Solving
16 + 8x + -1x2 = 28

Solving for variable 'x'.

Reorder the terms:
16 + -28 + 8x + -1x2 = 28 + -28

Combine like terms: 16 + -28 = -12
-12 + 8x + -1x2 = 28 + -28

Combine like terms: 28 + -28 = 0
-12 + 8x + -1x2 = 0

Factor a trinomial.
(-6 + x)(2 + -1x) = 0

Subproblem 1
Set the factor '(-6 + x)' equal to zero and attempt to solve:

Simplifying
-6 + x = 0

Solving
-6 + x = 0

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

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

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

Combine like terms: 0 + 6 = 6
x = 6

Simplifying
x = 6
Subproblem 2
Set the factor '(2 + -1x)' equal to zero and attempt to solve:

Simplifying
2 + -1x = 0

Solving
2 + -1x = 0

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

Add '-2' to each side of the equation.
2 + -2 + -1x = 0 + -2

Combine like terms: 2 + -2 = 0
0 + -1x = 0 + -2
-1x = 0 + -2

Combine like terms: 0 + -2 = -2
-1x = -2

Divide each side by '-1'.
x = 2

Simplifying
x = 2
Solution
x = {6, 2}