4c^2+15c+9=0

Solution for 4c^2+15c+9=0 equation:

Simplifying
4c2 + 15c + 9 = 0

Reorder the terms:
9 + 15c + 4c2 = 0

Solving
9 + 15c + 4c2 = 0

Solving for variable 'c'.

Factor a trinomial.
(3 + c)(3 + 4c) = 0

Subproblem 1
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
Subproblem 2
Set the factor '(3 + 4c)' equal to zero and attempt to solve:

Simplifying
3 + 4c = 0

Solving
3 + 4c = 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 + 4c = 0 + -3

Combine like terms: 3 + -3 = 0
0 + 4c = 0 + -3
4c = 0 + -3

Combine like terms: 0 + -3 = -3
4c = -3

Divide each side by '4'.
c = -0.75

Simplifying
c = -0.75
Solution
c = {-3, -0.75}