d^2+2d-120=0

Solution for d^2+2d-120=0 equation:

Simplifying
d2 + 2d + -120 = 0

Reorder the terms:
-120 + 2d + d2 = 0

Solving
-120 + 2d + d2 = 0

Solving for variable 'd'.

Factor a trinomial.
(-12 + -1d)(10 + -1d) = 0

Subproblem 1
Set the factor '(-12 + -1d)' equal to zero and attempt to solve:

Simplifying
-12 + -1d = 0

Solving
-12 + -1d = 0

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

Add '12' to each side of the equation.
-12 + 12 + -1d = 0 + 12

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

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

Divide each side by '-1'.
d = -12

Simplifying
d = -12
Subproblem 2
Set the factor '(10 + -1d)' equal to zero and attempt to solve:

Simplifying
10 + -1d = 0

Solving
10 + -1d = 0

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

Add '-10' to each side of the equation.
10 + -10 + -1d = 0 + -10

Combine like terms: 10 + -10 = 0
0 + -1d = 0 + -10
-1d = 0 + -10

Combine like terms: 0 + -10 = -10
-1d = -10

Divide each side by '-1'.
d = 10

Simplifying
d = 10
Solution
d = {-12, 10}