100=4x(4x+x)

Solution for 100=4x(4x+x) equation:

Simplifying
100 = 4x(4x + x)

Combine like terms: 4x + x = 5x
100 = 4x(5x)

Remove parenthesis around (5x)
100 = 4x * 5x

Reorder the terms for easier multiplication:
100 = 4 * 5x * x

Multiply 4 * 5
100 = 20x * x

Multiply x * x
100 = 20x2

Solving
100 = 20x2

Solving for variable 'x'.

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

Add '-20x2' to each side of the equation.
100 + -20x2 = 20x2 + -20x2

Combine like terms: 20x2 + -20x2 = 0
100 + -20x2 = 0

Add '-100' to each side of the equation.
100 + -100 + -20x2 = 0 + -100

Combine like terms: 100 + -100 = 0
0 + -20x2 = 0 + -100
-20x2 = 0 + -100

Combine like terms: 0 + -100 = -100
-20x2 = -100

Divide each side by '-20'.
x2 = 5

Simplifying
x2 = 5

Take the square root of each side:
x = {-2.236067978, 2.236067978}