f^2+9f+18=0

Solution for f^2+9f+18=0 equation:

Simplifying
f2 + 9f + 18 = 0

Reorder the terms:
18 + 9f + f2 = 0

Solving
18 + 9f + f2 = 0

Solving for variable 'f'.

Factor a trinomial.
(6 + f)(3 + f) = 0

Subproblem 1
Set the factor '(6 + f)' equal to zero and attempt to solve:

Simplifying
6 + f = 0

Solving
6 + f = 0

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

Add '-6' to each side of the equation.
6 + -6 + f = 0 + -6

Combine like terms: 6 + -6 = 0
0 + f = 0 + -6
f = 0 + -6

Combine like terms: 0 + -6 = -6
f = -6

Simplifying
f = -6
Subproblem 2
Set the factor '(3 + f)' equal to zero and attempt to solve:

Simplifying
3 + f = 0

Solving
3 + f = 0

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

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

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

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

Simplifying
f = -3
Solution
f = {-6, -3}