18=-4n^2-18n

Solution for 18=-4n^2-18n equation:

Simplifying
18 = -4n2 + -18n

Reorder the terms:
18 = -18n + -4n2

Solving
18 = -18n + -4n2

Solving for variable 'n'.

Reorder the terms:
18 + 18n + 4n2 = -18n + 18n + -4n2 + 4n2

Combine like terms: -18n + 18n = 0
18 + 18n + 4n2 = 0 + -4n2 + 4n2
18 + 18n + 4n2 = -4n2 + 4n2

Combine like terms: -4n2 + 4n2 = 0
18 + 18n + 4n2 = 0

Factor out the Greatest Common Factor (GCF), '2'.
2(9 + 9n + 2n2) = 0

Factor a trinomial.
2((3 + n)(3 + 2n)) = 0

Ignore the factor 2.
Subproblem 1
Set the factor '(3 + n)' equal to zero and attempt to solve:

Simplifying
3 + n = 0

Solving
3 + n = 0

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

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

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

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

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

Simplifying
3 + 2n = 0

Solving
3 + 2n = 0

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

Add '-3' to each side of the equation.
3 + -3 + 2n = 0 + -3

Combine like terms: 3 + -3 = 0
0 + 2n = 0 + -3
2n = 0 + -3

Combine like terms: 0 + -3 = -3
2n = -3

Divide each side by '2'.
n = -1.5

Simplifying
n = -1.5
Solution
n = {-3, -1.5}