8d^2+28d+12=0

Solution for 8d^2+28d+12=0 equation:

Simplifying
8d2 + 28d + 12 = 0

Reorder the terms:
12 + 28d + 8d2 = 0

Solving
12 + 28d + 8d2 = 0

Solving for variable 'd'.

Factor out the Greatest Common Factor (GCF), '4'.
4(3 + 7d + 2d2) = 0

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

Ignore the factor 4.
Subproblem 1
Set the factor '(3 + d)' equal to zero and attempt to solve:

Simplifying
3 + d = 0

Solving
3 + d = 0

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

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

Combine like terms: 3 + -3 = 0
0 + d = 0 + -3
d = 0 + -3

Combine like terms: 0 + -3 = -3
d = -3

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

Simplifying
1 + 2d = 0

Solving
1 + 2d = 0

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

Add '-1' to each side of the equation.
1 + -1 + 2d = 0 + -1

Combine like terms: 1 + -1 = 0
0 + 2d = 0 + -1
2d = 0 + -1

Combine like terms: 0 + -1 = -1
2d = -1

Divide each side by '2'.
d = -0.5

Simplifying
d = -0.5
Solution
d = {-3, -0.5}