0=d^2-d-12

Solution for 0=d^2-d-12 equation:

Simplifying
0 = d2 + -1d + -12

Reorder the terms:
0 = -12 + -1d + d2

Solving
0 = -12 + -1d + d2

Solving for variable 'd'.

Combine like terms: 0 + 12 = 12
12 + d + -1d2 = -12 + -1d + d2 + 12 + d + -1d2

Reorder the terms:
12 + d + -1d2 = -12 + 12 + -1d + d + d2 + -1d2

Combine like terms: -12 + 12 = 0
12 + d + -1d2 = 0 + -1d + d + d2 + -1d2
12 + d + -1d2 = -1d + d + d2 + -1d2

Combine like terms: -1d + d = 0
12 + d + -1d2 = 0 + d2 + -1d2
12 + d + -1d2 = d2 + -1d2

Combine like terms: d2 + -1d2 = 0
12 + d + -1d2 = 0

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

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

Simplifying
4 + -1d = 0

Solving
4 + -1d = 0

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

Add '-4' to each side of the equation.
4 + -4 + -1d = 0 + -4

Combine like terms: 4 + -4 = 0
0 + -1d = 0 + -4
-1d = 0 + -4

Combine like terms: 0 + -4 = -4
-1d = -4

Divide each side by '-1'.
d = 4

Simplifying
d = 4
Subproblem 2
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
Solution
d = {4, -3}