20=w(w-8)

Solution for 20=w(w-8) equation:

Simplifying
20 = w(w + -8)

Reorder the terms:
20 = w(-8 + w)
20 = (-8 * w + w * w)
20 = (-8w + w2)

Solving
20 = -8w + w2

Solving for variable 'w'.

Reorder the terms:
20 + 8w + -1w2 = -8w + 8w + w2 + -1w2

Combine like terms: -8w + 8w = 0
20 + 8w + -1w2 = 0 + w2 + -1w2
20 + 8w + -1w2 = w2 + -1w2

Combine like terms: w2 + -1w2 = 0
20 + 8w + -1w2 = 0

Factor a trinomial.
(10 + -1w)(2 + w) = 0

Subproblem 1
Set the factor '(10 + -1w)' equal to zero and attempt to solve:

Simplifying
10 + -1w = 0

Solving
10 + -1w = 0

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

Add '-10' to each side of the equation.
10 + -10 + -1w = 0 + -10

Combine like terms: 10 + -10 = 0
0 + -1w = 0 + -10
-1w = 0 + -10

Combine like terms: 0 + -10 = -10
-1w = -10

Divide each side by '-1'.
w = 10

Simplifying
w = 10
Subproblem 2
Set the factor '(2 + w)' equal to zero and attempt to solve:

Simplifying
2 + w = 0

Solving
2 + w = 0

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

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

Combine like terms: 2 + -2 = 0
0 + w = 0 + -2
w = 0 + -2

Combine like terms: 0 + -2 = -2
w = -2

Simplifying
w = -2
Solution
w = {10, -2}