(d-8)(2d+5)=0

Solution for (d-8)(2d+5)=0 equation:

Simplifying
(d + -8)(2d + 5) = 0

Reorder the terms:
(-8 + d)(2d + 5) = 0

Reorder the terms:
(-8 + d)(5 + 2d) = 0

Multiply (-8 + d) * (5 + 2d)
(-8(5 + 2d) + d(5 + 2d)) = 0
((5 * -8 + 2d * -8) + d(5 + 2d)) = 0
((-40 + -16d) + d(5 + 2d)) = 0
(-40 + -16d + (5 * d + 2d * d)) = 0
(-40 + -16d + (5d + 2d2)) = 0

Combine like terms: -16d + 5d = -11d
(-40 + -11d + 2d2) = 0

Solving
-40 + -11d + 2d2 = 0

Solving for variable 'd'.

Factor a trinomial.
(-5 + -2d)(8 + -1d) = 0

Subproblem 1
Set the factor '(-5 + -2d)' equal to zero and attempt to solve:

Simplifying
-5 + -2d = 0

Solving
-5 + -2d = 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 + -2d = 0 + 5

Combine like terms: -5 + 5 = 0
0 + -2d = 0 + 5
-2d = 0 + 5

Combine like terms: 0 + 5 = 5
-2d = 5

Divide each side by '-2'.
d = -2.5

Simplifying
d = -2.5
Subproblem 2
Set the factor '(8 + -1d)' equal to zero and attempt to solve:

Simplifying
8 + -1d = 0

Solving
8 + -1d = 0

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

Add '-8' to each side of the equation.
8 + -8 + -1d = 0 + -8

Combine like terms: 8 + -8 = 0
0 + -1d = 0 + -8
-1d = 0 + -8

Combine like terms: 0 + -8 = -8
-1d = -8

Divide each side by '-1'.
d = 8

Simplifying
d = 8
Solution
d = {-2.5, 8}