15=(x+6)(x-8)

Solution for 15=(x+6)(x-8) equation:

Simplifying
15 = (x + 6)(x + -8)

Reorder the terms:
15 = (6 + x)(x + -8)

Reorder the terms:
15 = (6 + x)(-8 + x)

Multiply (6 + x) * (-8 + x)
15 = (6(-8 + x) + x(-8 + x))
15 = ((-8 * 6 + x * 6) + x(-8 + x))
15 = ((-48 + 6x) + x(-8 + x))
15 = (-48 + 6x + (-8 * x + x * x))
15 = (-48 + 6x + (-8x + x2))

Combine like terms: 6x + -8x = -2x
15 = (-48 + -2x + x2)

Solving
15 = -48 + -2x + x2

Solving for variable 'x'.

Combine like terms: 15 + 48 = 63
63 + 2x + -1x2 = -48 + -2x + x2 + 48 + 2x + -1x2

Reorder the terms:
63 + 2x + -1x2 = -48 + 48 + -2x + 2x + x2 + -1x2

Combine like terms: -48 + 48 = 0
63 + 2x + -1x2 = 0 + -2x + 2x + x2 + -1x2
63 + 2x + -1x2 = -2x + 2x + x2 + -1x2

Combine like terms: -2x + 2x = 0
63 + 2x + -1x2 = 0 + x2 + -1x2
63 + 2x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
63 + 2x + -1x2 = 0

Factor a trinomial.
(9 + -1x)(7 + x) = 0

Subproblem 1
Set the factor '(9 + -1x)' equal to zero and attempt to solve:

Simplifying
9 + -1x = 0

Solving
9 + -1x = 0

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

Add '-9' to each side of the equation.
9 + -9 + -1x = 0 + -9

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

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

Divide each side by '-1'.
x = 9

Simplifying
x = 9
Subproblem 2
Set the factor '(7 + x)' equal to zero and attempt to solve:

Simplifying
7 + x = 0

Solving
7 + x = 0

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

Add '-7' to each side of the equation.
7 + -7 + x = 0 + -7

Combine like terms: 7 + -7 = 0
0 + x = 0 + -7
x = 0 + -7

Combine like terms: 0 + -7 = -7
x = -7

Simplifying
x = -7
Solution
x = {9, -7}