64=(k+6)(k-6)

Solution for 64=(k+6)(k-6) equation:

Simplifying
64 = (k + 6)(k + -6)

Reorder the terms:
64 = (6 + k)(k + -6)

Reorder the terms:
64 = (6 + k)(-6 + k)

Multiply (6 + k) * (-6 + k)
64 = (6(-6 + k) + k(-6 + k))
64 = ((-6 * 6 + k * 6) + k(-6 + k))
64 = ((-36 + 6k) + k(-6 + k))
64 = (-36 + 6k + (-6 * k + k * k))
64 = (-36 + 6k + (-6k + k2))

Combine like terms: 6k + -6k = 0
64 = (-36 + 0 + k2)
64 = (-36 + k2)

Solving
64 = -36 + k2

Solving for variable 'k'.

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

Add '-1k2' to each side of the equation.
64 + -1k2 = -36 + k2 + -1k2

Combine like terms: k2 + -1k2 = 0
64 + -1k2 = -36 + 0
64 + -1k2 = -36

Add '-64' to each side of the equation.
64 + -64 + -1k2 = -36 + -64

Combine like terms: 64 + -64 = 0
0 + -1k2 = -36 + -64
-1k2 = -36 + -64

Combine like terms: -36 + -64 = -100
-1k2 = -100

Divide each side by '-1'.
k2 = 100

Simplifying
k2 = 100

Take the square root of each side:
k = {-10, 10}