1-16=(x+4)(x-4)

Solution for 1-16=(x+4)(x-4) equation:

Simplifying
1 + -16 = (x + 4)(x + -4)

Combine like terms: 1 + -16 = -15
-15 = (x + 4)(x + -4)

Reorder the terms:
-15 = (4 + x)(x + -4)

Reorder the terms:
-15 = (4 + x)(-4 + x)

Multiply (4 + x) * (-4 + x)
-15 = (4(-4 + x) + x(-4 + x))
-15 = ((-4 * 4 + x * 4) + x(-4 + x))
-15 = ((-16 + 4x) + x(-4 + x))
-15 = (-16 + 4x + (-4 * x + x * x))
-15 = (-16 + 4x + (-4x + x2))

Combine like terms: 4x + -4x = 0
-15 = (-16 + 0 + x2)
-15 = (-16 + x2)

Solving
-15 = -16 + x2

Solving for variable 'x'.

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

Add '-1x2' to each side of the equation.
-15 + -1x2 = -16 + x2 + -1x2

Combine like terms: x2 + -1x2 = 0
-15 + -1x2 = -16 + 0
-15 + -1x2 = -16

Add '15' to each side of the equation.
-15 + 15 + -1x2 = -16 + 15

Combine like terms: -15 + 15 = 0
0 + -1x2 = -16 + 15
-1x2 = -16 + 15

Combine like terms: -16 + 15 = -1
-1x2 = -1

Divide each side by '-1'.
x2 = 1

Simplifying
x2 = 1

Take the square root of each side:
x = {-1, 1}