d^2+16d+55=0

Solution for d^2+16d+55=0 equation:

Simplifying
d2 + 16d + 55 = 0

Reorder the terms:
55 + 16d + d2 = 0

Solving
55 + 16d + d2 = 0

Solving for variable 'd'.

Factor a trinomial.
(11 + d)(5 + d) = 0

Subproblem 1
Set the factor '(11 + d)' equal to zero and attempt to solve:

Simplifying
11 + d = 0

Solving
11 + d = 0

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

Add '-11' to each side of the equation.
11 + -11 + d = 0 + -11

Combine like terms: 11 + -11 = 0
0 + d = 0 + -11
d = 0 + -11

Combine like terms: 0 + -11 = -11
d = -11

Simplifying
d = -11
Subproblem 2
Set the factor '(5 + d)' equal to zero and attempt to solve:

Simplifying
5 + d = 0

Solving
5 + d = 0

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

Add '-5' to each side of the equation.
5 + -5 + d = 0 + -5

Combine like terms: 5 + -5 = 0
0 + d = 0 + -5
d = 0 + -5

Combine like terms: 0 + -5 = -5
d = -5

Simplifying
d = -5
Solution
d = {-11, -5}