x*x+9x=-20

Solution for x*x+9x=-20 equation:

Simplifying
x * x + 9x = -20

Multiply x * x
x2 + 9x = -20

Reorder the terms:
9x + x2 = -20

Solving
9x + x2 = -20

Solving for variable 'x'.

Reorder the terms:
20 + 9x + x2 = -20 + 20

Combine like terms: -20 + 20 = 0
20 + 9x + x2 = 0

Factor a trinomial.
(5 + x)(4 + x) = 0

Subproblem 1
Set the factor '(5 + x)' equal to zero and attempt to solve:

Simplifying
5 + x = 0

Solving
5 + x = 0

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

Add '-5' to each side of the equation.
5 + -5 + x = 0 + -5

Combine like terms: 5 + -5 = 0
0 + x = 0 + -5
x = 0 + -5

Combine like terms: 0 + -5 = -5
x = -5

Simplifying
x = -5
Subproblem 2
Set the factor '(4 + x)' equal to zero and attempt to solve:

Simplifying
4 + x = 0

Solving
4 + x = 0

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

Add '-4' to each side of the equation.
4 + -4 + x = 0 + -4

Combine like terms: 4 + -4 = 0
0 + x = 0 + -4
x = 0 + -4

Combine like terms: 0 + -4 = -4
x = -4

Simplifying
x = -4
Solution
x = {-5, -4}