-12r^2-20r-8=0

Solution for -12r^2-20r-8=0 equation:

Simplifying
-12r2 + -20r + -8 = 0

Reorder the terms:
-8 + -20r + -12r2 = 0

Solving
-8 + -20r + -12r2 = 0

Solving for variable 'r'.

Factor out the Greatest Common Factor (GCF), '-4'.
-4(2 + 5r + 3r2) = 0

Factor a trinomial.
-4((1 + r)(2 + 3r)) = 0

Ignore the factor -4.
Subproblem 1
Set the factor '(1 + r)' equal to zero and attempt to solve:

Simplifying
1 + r = 0

Solving
1 + r = 0

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

Add '-1' to each side of the equation.
1 + -1 + r = 0 + -1

Combine like terms: 1 + -1 = 0
0 + r = 0 + -1
r = 0 + -1

Combine like terms: 0 + -1 = -1
r = -1

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

Simplifying
2 + 3r = 0

Solving
2 + 3r = 0

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

Add '-2' to each side of the equation.
2 + -2 + 3r = 0 + -2

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

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

Divide each side by '3'.
r = -0.6666666667

Simplifying
r = -0.6666666667
Solution
r = {-1, -0.6666666667}