20c^2+13c-15=0

Solution for 20c^2+13c-15=0 equation:

Simplifying
20c2 + 13c + -15 = 0

Reorder the terms:
-15 + 13c + 20c2 = 0

Solving
-15 + 13c + 20c2 = 0

Solving for variable 'c'.

Factor a trinomial.
(-5 + -4c)(3 + -5c) = 0

Subproblem 1
Set the factor '(-5 + -4c)' equal to zero and attempt to solve:

Simplifying
-5 + -4c = 0

Solving
-5 + -4c = 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 + -4c = 0 + 5

Combine like terms: -5 + 5 = 0
0 + -4c = 0 + 5
-4c = 0 + 5

Combine like terms: 0 + 5 = 5
-4c = 5

Divide each side by '-4'.
c = -1.25

Simplifying
c = -1.25
Subproblem 2
Set the factor '(3 + -5c)' equal to zero and attempt to solve:

Simplifying
3 + -5c = 0

Solving
3 + -5c = 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 + -5c = 0 + -3

Combine like terms: 3 + -3 = 0
0 + -5c = 0 + -3
-5c = 0 + -3

Combine like terms: 0 + -3 = -3
-5c = -3

Divide each side by '-5'.
c = 0.6

Simplifying
c = 0.6
Solution
c = {-1.25, 0.6}