c(c)+8c+15=0

Solution for c(c)+8c+15=0 equation:

Simplifying
c(c) + 8c + 15 = 0

Multiply c * c
c2 + 8c + 15 = 0

Reorder the terms:
15 + 8c + c2 = 0

Solving
15 + 8c + c2 = 0

Solving for variable 'c'.

Factor a trinomial.
(5 + c)(3 + c) = 0

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

Simplifying
5 + c = 0

Solving
5 + c = 0

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

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

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

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

Simplifying
c = -5
Subproblem 2
Set the factor '(3 + c)' equal to zero and attempt to solve:

Simplifying
3 + c = 0

Solving
3 + c = 0

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

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

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

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

Simplifying
c = -3
Solution
c = {-5, -3}