4c^2-4c=15

Solution for 4c^2-4c=15 equation:

Simplifying
4c2 + -4c = 15

Reorder the terms:
-4c + 4c2 = 15

Solving
-4c + 4c2 = 15

Solving for variable 'c'.

Reorder the terms:
-15 + -4c + 4c2 = 15 + -15

Combine like terms: 15 + -15 = 0
-15 + -4c + 4c2 = 0

Factor a trinomial.
(-3 + -2c)(5 + -2c) = 0

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

Simplifying
-3 + -2c = 0

Solving
-3 + -2c = 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 + -2c = 0 + 3

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

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

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

Simplifying
c = -1.5
Subproblem 2
Set the factor '(5 + -2c)' equal to zero and attempt to solve:

Simplifying
5 + -2c = 0

Solving
5 + -2c = 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 + -2c = 0 + -5

Combine like terms: 5 + -5 = 0
0 + -2c = 0 + -5
-2c = 0 + -5

Combine like terms: 0 + -5 = -5
-2c = -5

Divide each side by '-2'.
c = 2.5

Simplifying
c = 2.5
Solution
c = {-1.5, 2.5}