x=(30-2x)(20-2x)x

Solution for x=(30-2x)(20-2x)x equation:

Simplifying
x = (30 + -2x)(20 + -2x) * x

Reorder the terms for easier multiplication:
x = x(30 + -2x)(20 + -2x)

Multiply (30 + -2x) * (20 + -2x)
x = x(30(20 + -2x) + -2x * (20 + -2x))
x = x((20 * 30 + -2x * 30) + -2x * (20 + -2x))
x = x((600 + -60x) + -2x * (20 + -2x))
x = x(600 + -60x + (20 * -2x + -2x * -2x))
x = x(600 + -60x + (-40x + 4x2))

Combine like terms: -60x + -40x = -100x
x = x(600 + -100x + 4x2)
x = (600 * x + -100x * x + 4x2 * x)
x = (600x + -100x2 + 4x3)

Solving
x = 600x + -100x2 + 4x3

Solving for variable 'x'.

Combine like terms: x + -600x = -599x
-599x + 100x2 + -4x3 = 600x + -100x2 + 4x3 + -600x + 100x2 + -4x3

Reorder the terms:
-599x + 100x2 + -4x3 = 600x + -600x + -100x2 + 100x2 + 4x3 + -4x3

Combine like terms: 600x + -600x = 0
-599x + 100x2 + -4x3 = 0 + -100x2 + 100x2 + 4x3 + -4x3
-599x + 100x2 + -4x3 = -100x2 + 100x2 + 4x3 + -4x3

Combine like terms: -100x2 + 100x2 = 0
-599x + 100x2 + -4x3 = 0 + 4x3 + -4x3
-599x + 100x2 + -4x3 = 4x3 + -4x3

Combine like terms: 4x3 + -4x3 = 0
-599x + 100x2 + -4x3 = 0

Factor out the Greatest Common Factor (GCF), 'x'.
x(-599 + 100x + -4x2) = 0

Subproblem 1
Set the factor 'x' equal to zero and attempt to solve:

Simplifying
x = 0

Solving
x = 0

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

Simplifying
x = 0
Subproblem 2
Set the factor '(-599 + 100x + -4x2)' equal to zero and attempt to solve:

Simplifying
-599 + 100x + -4x2 = 0

Solving
-599 + 100x + -4x2 = 0

Begin completing the square.  Divide all terms by
-4 the coefficient of the squared term: 

Divide each side by '-4'.
149.75 + -25x + x2 = 0

Move the constant term to the right:

Add '-149.75' to each side of the equation.
149.75 + -25x + -149.75 + x2 = 0 + -149.75

Reorder the terms:
149.75 + -149.75 + -25x + x2 = 0 + -149.75

Combine like terms: 149.75 + -149.75 = 0.00
0.00 + -25x + x2 = 0 + -149.75
-25x + x2 = 0 + -149.75

Combine like terms: 0 + -149.75 = -149.75
-25x + x2 = -149.75

The x term is -25x.  Take half its coefficient (-12.5).
Square it (156.25) and add it to both sides.

Add '156.25' to each side of the equation.
-25x + 156.25 + x2 = -149.75 + 156.25

Reorder the terms:
156.25 + -25x + x2 = -149.75 + 156.25

Combine like terms: -149.75 + 156.25 = 6.5
156.25 + -25x + x2 = 6.5

Factor a perfect square on the left side:
(x + -12.5)(x + -12.5) = 6.5

Calculate the square root of the right side: 2.549509757

Break this problem into two subproblems by setting 
(x + -12.5) equal to 2.549509757 and -2.549509757.

Subproblem 1
x + -12.5 = 2.549509757

Simplifying
x + -12.5 = 2.549509757

Reorder the terms:
-12.5 + x = 2.549509757

Solving
-12.5 + x = 2.549509757

Solving for variable 'x'.

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

Add '12.5' to each side of the equation.
-12.5 + 12.5 + x = 2.549509757 + 12.5

Combine like terms: -12.5 + 12.5 = 0.0
0.0 + x = 2.549509757 + 12.5
x = 2.549509757 + 12.5

Combine like terms: 2.549509757 + 12.5 = 15.049509757
x = 15.049509757

Simplifying
x = 15.049509757

Subproblem 2
x + -12.5 = -2.549509757

Simplifying
x + -12.5 = -2.549509757

Reorder the terms:
-12.5 + x = -2.549509757

Solving
-12.5 + x = -2.549509757

Solving for variable 'x'.

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

Add '12.5' to each side of the equation.
-12.5 + 12.5 + x = -2.549509757 + 12.5

Combine like terms: -12.5 + 12.5 = 0.0
0.0 + x = -2.549509757 + 12.5
x = -2.549509757 + 12.5

Combine like terms: -2.549509757 + 12.5 = 9.950490243
x = 9.950490243

Simplifying
x = 9.950490243

Solution
The solution to the problem is based on the solutions
from the subproblems.
x = {15.049509757, 9.950490243}
Solution
x = {0, 15.049509757, 9.950490243}