(x-5)(4x-20)=

Solution for (x-5)(4x-20)= equation:

Simplifying
(x + -5)(4x + -20) = 0

Reorder the terms:
(-5 + x)(4x + -20) = 0

Reorder the terms:
(-5 + x)(-20 + 4x) = 0

Multiply (-5 + x) * (-20 + 4x)
(-5(-20 + 4x) + x(-20 + 4x)) = 0
((-20 * -5 + 4x * -5) + x(-20 + 4x)) = 0
((100 + -20x) + x(-20 + 4x)) = 0
(100 + -20x + (-20 * x + 4x * x)) = 0
(100 + -20x + (-20x + 4x2)) = 0

Combine like terms: -20x + -20x = -40x
(100 + -40x + 4x2) = 0

Solving
100 + -40x + 4x2 = 0

Solving for variable 'x'.

Factor out the Greatest Common Factor (GCF), '4'.
4(25 + -10x + x2) = 0

Factor a trinomial.
4((5 + -1x)(5 + -1x)) = 0

Ignore the factor 4.
Subproblem 1
Set the factor '(5 + -1x)' equal to zero and attempt to solve:

Simplifying
5 + -1x = 0

Solving
5 + -1x = 0

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

Add '-5' to each side of the equation.
5 + -5 + -1x = 0 + -5

Combine like terms: 5 + -5 = 0
0 + -1x = 0 + -5
-1x = 0 + -5

Combine like terms: 0 + -5 = -5
-1x = -5

Divide each side by '-1'.
x = 5

Simplifying
x = 5
Subproblem 2
Set the factor '(5 + -1x)' equal to zero and attempt to solve:

Simplifying
5 + -1x = 0

Solving
5 + -1x = 0

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

Add '-5' to each side of the equation.
5 + -5 + -1x = 0 + -5

Combine like terms: 5 + -5 = 0
0 + -1x = 0 + -5
-1x = 0 + -5

Combine like terms: 0 + -5 = -5
-1x = -5

Divide each side by '-1'.
x = 5

Simplifying
x = 5
Solution
x = {5, 5}