2c(-c-12)=-2c-12

Solution for 2c(-c-12)=-2c-12 equation:

Simplifying
2c(-1c + -12) = -2c + -12

Reorder the terms:
2c(-12 + -1c) = -2c + -12
(-12 * 2c + -1c * 2c) = -2c + -12
(-24c + -2c2) = -2c + -12

Reorder the terms:
-24c + -2c2 = -12 + -2c

Solving
-24c + -2c2 = -12 + -2c

Solving for variable 'c'.

Reorder the terms:
12 + -24c + 2c + -2c2 = -12 + -2c + 12 + 2c

Combine like terms: -24c + 2c = -22c
12 + -22c + -2c2 = -12 + -2c + 12 + 2c

Reorder the terms:
12 + -22c + -2c2 = -12 + 12 + -2c + 2c

Combine like terms: -12 + 12 = 0
12 + -22c + -2c2 = 0 + -2c + 2c
12 + -22c + -2c2 = -2c + 2c

Combine like terms: -2c + 2c = 0
12 + -22c + -2c2 = 0

Factor out the Greatest Common Factor (GCF), '2'.
2(6 + -11c + -1c2) = 0

Ignore the factor 2.
Subproblem 1
Set the factor '(6 + -11c + -1c2)' equal to zero and attempt to solve:

Simplifying
6 + -11c + -1c2 = 0

Solving
6 + -11c + -1c2 = 0

Begin completing the square.  Divide all terms by
-1 the coefficient of the squared term: 

Divide each side by '-1'.
-6 + 11c + c2 = 0

Move the constant term to the right:

Add '6' to each side of the equation.
-6 + 11c + 6 + c2 = 0 + 6

Reorder the terms:
-6 + 6 + 11c + c2 = 0 + 6

Combine like terms: -6 + 6 = 0
0 + 11c + c2 = 0 + 6
11c + c2 = 0 + 6

Combine like terms: 0 + 6 = 6
11c + c2 = 6

The c term is 11c.  Take half its coefficient (5.5).
Square it (30.25) and add it to both sides.

Add '30.25' to each side of the equation.
11c + 30.25 + c2 = 6 + 30.25

Reorder the terms:
30.25 + 11c + c2 = 6 + 30.25

Combine like terms: 6 + 30.25 = 36.25
30.25 + 11c + c2 = 36.25

Factor a perfect square on the left side:
(c + 5.5)(c + 5.5) = 36.25

Calculate the square root of the right side: 6.020797289

Break this problem into two subproblems by setting 
(c + 5.5) equal to 6.020797289 and -6.020797289.

Subproblem 1
c + 5.5 = 6.020797289

Simplifying
c + 5.5 = 6.020797289

Reorder the terms:
5.5 + c = 6.020797289

Solving
5.5 + c = 6.020797289

Solving for variable 'c'.

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

Add '-5.5' to each side of the equation.
5.5 + -5.5 + c = 6.020797289 + -5.5

Combine like terms: 5.5 + -5.5 = 0.0
0.0 + c = 6.020797289 + -5.5
c = 6.020797289 + -5.5

Combine like terms: 6.020797289 + -5.5 = 0.520797289
c = 0.520797289

Simplifying
c = 0.520797289

Subproblem 2
c + 5.5 = -6.020797289

Simplifying
c + 5.5 = -6.020797289

Reorder the terms:
5.5 + c = -6.020797289

Solving
5.5 + c = -6.020797289

Solving for variable 'c'.

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

Add '-5.5' to each side of the equation.
5.5 + -5.5 + c = -6.020797289 + -5.5

Combine like terms: 5.5 + -5.5 = 0.0
0.0 + c = -6.020797289 + -5.5
c = -6.020797289 + -5.5

Combine like terms: -6.020797289 + -5.5 = -11.520797289
c = -11.520797289

Simplifying
c = -11.520797289

Solution
The solution to the problem is based on the solutions
from the subproblems.
c = {0.520797289, -11.520797289}
Solution
c = {0.520797289, -11.520797289}