-9=y(y+6)

Solution for -9=y(y+6) equation:

Simplifying
-9 = y(y + 6)

Reorder the terms:
-9 = y(6 + y)
-9 = (6 * y + y * y)
-9 = (6y + y2)

Solving
-9 = 6y + y2

Solving for variable 'y'.

Reorder the terms:
-9 + -6y + -1y2 = 6y + -6y + y2 + -1y2

Combine like terms: 6y + -6y = 0
-9 + -6y + -1y2 = 0 + y2 + -1y2
-9 + -6y + -1y2 = y2 + -1y2

Combine like terms: y2 + -1y2 = 0
-9 + -6y + -1y2 = 0

Factor out the Greatest Common Factor (GCF), '-1'.
-1(9 + 6y + y2) = 0

Factor a trinomial.
-1((3 + y)(3 + y)) = 0

Ignore the factor -1.
Subproblem 1
Set the factor '(3 + y)' equal to zero and attempt to solve:

Simplifying
3 + y = 0

Solving
3 + y = 0

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

Add '-3' to each side of the equation.
3 + -3 + y = 0 + -3

Combine like terms: 3 + -3 = 0
0 + y = 0 + -3
y = 0 + -3

Combine like terms: 0 + -3 = -3
y = -3

Simplifying
y = -3
Subproblem 2
Set the factor '(3 + y)' equal to zero and attempt to solve:

Simplifying
3 + y = 0

Solving
3 + y = 0

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

Add '-3' to each side of the equation.
3 + -3 + y = 0 + -3

Combine like terms: 3 + -3 = 0
0 + y = 0 + -3
y = 0 + -3

Combine like terms: 0 + -3 = -3
y = -3

Simplifying
y = -3
Solution
y = {-3, -3}