400=x*42x

Solution for 400=x*42x equation:

Simplifying
400 = x * 42x

Reorder the terms for easier multiplication:
400 = 42x * x

Multiply x * x
400 = 42x2

Solving
400 = 42x2

Solving for variable 'x'.

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

Add '-42x2' to each side of the equation.
400 + -42x2 = 42x2 + -42x2

Combine like terms: 42x2 + -42x2 = 0
400 + -42x2 = 0

Add '-400' to each side of the equation.
400 + -400 + -42x2 = 0 + -400

Combine like terms: 400 + -400 = 0
0 + -42x2 = 0 + -400
-42x2 = 0 + -400

Combine like terms: 0 + -400 = -400
-42x2 = -400

Divide each side by '-42'.
x2 = 9.523809524

Simplifying
x2 = 9.523809524

Take the square root of each side:
x = {-3.086066999, 3.086066999}