400x+x^2=0

Solution for 400x+x^2=0 equation:

Simplifying
400x + x2 = 0

Solving
400x + x2 = 0

Solving for variable 'x'.

Factor out the Greatest Common Factor (GCF), 'x'.
x(400 + x) = 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 '(400 + x)' equal to zero and attempt to solve:

Simplifying
400 + x = 0

Solving
400 + x = 0

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

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

Combine like terms: 400 + -400 = 0
0 + x = 0 + -400
x = 0 + -400

Combine like terms: 0 + -400 = -400
x = -400

Simplifying
x = -400
Solution
x = {0, -400}