x^2+4.2x=0

Solution for x^2+4.2x=0 equation:

Simplifying
x2 + 4.2x = 0

Reorder the terms:
4.2x + x2 = 0

Solving
4.2x + x2 = 0

Solving for variable 'x'.

Factor out the Greatest Common Factor (GCF), 'x'.
x(4.2 + 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 '(4.2 + x)' equal to zero and attempt to solve:

Simplifying
4.2 + x = 0

Solving
4.2 + x = 0

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

Add '-4.2' to each side of the equation.
4.2 + -4.2 + x = 0 + -4.2

Combine like terms: 4.2 + -4.2 = 0.0
0.0 + x = 0 + -4.2
x = 0 + -4.2

Combine like terms: 0 + -4.2 = -4.2
x = -4.2

Simplifying
x = -4.2
Solution
x = {0, -4.2}