(9x)(x-4)=0

Solution for (9x)(x-4)=0 equation:

Simplifying
(9x)(x + -4) = 0

Remove parenthesis around (9x)
9x(x + -4) = 0

Reorder the terms:
9x(-4 + x) = 0
(-4 * 9x + x * 9x) = 0
(-36x + 9x2) = 0

Solving
-36x + 9x2 = 0

Solving for variable 'x'.

Factor out the Greatest Common Factor (GCF), '9x'.
9x(-4 + x) = 0

Ignore the factor 9.
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 '(-4 + x)' equal to zero and attempt to solve:

Simplifying
-4 + x = 0

Solving
-4 + x = 0

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

Add '4' to each side of the equation.
-4 + 4 + x = 0 + 4

Combine like terms: -4 + 4 = 0
0 + x = 0 + 4
x = 0 + 4

Combine like terms: 0 + 4 = 4
x = 4

Simplifying
x = 4
Solution
x = {0, 4}