13000=x(x*.3)

Solution for 13000=x(x*.3) equation:

Simplifying
13000 = x(x * 0.3)

Reorder the terms for easier multiplication:
13000 = x(0.3x)

Remove parenthesis around (0.3x)
13000 = x * 0.3x

Reorder the terms for easier multiplication:
13000 = 0.3x * x

Multiply x * x
13000 = 0.3x2

Solving
13000 = 0.3x2

Solving for variable 'x'.

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

Add '-0.3x2' to each side of the equation.
13000 + -0.3x2 = 0.3x2 + -0.3x2

Combine like terms: 0.3x2 + -0.3x2 = 0.0
13000 + -0.3x2 = 0.0

Add '-13000' to each side of the equation.
13000 + -13000 + -0.3x2 = 0.0 + -13000

Combine like terms: 13000 + -13000 = 0
0 + -0.3x2 = 0.0 + -13000
-0.3x2 = 0.0 + -13000

Combine like terms: 0.0 + -13000 = -13000
-0.3x2 = -13000

Divide each side by '-0.3'.
x2 = 43333.33333

Simplifying
x2 = 43333.33333

Take the square root of each side:
x = {-208.166599939, 208.166599939}