(d-4)(2d+7)=0

Solution for (d-4)(2d+7)=0 equation:

Simplifying
(d + -4)(2d + 7) = 0

Reorder the terms:
(-4 + d)(2d + 7) = 0

Reorder the terms:
(-4 + d)(7 + 2d) = 0

Multiply (-4 + d) * (7 + 2d)
(-4(7 + 2d) + d(7 + 2d)) = 0
((7 * -4 + 2d * -4) + d(7 + 2d)) = 0
((-28 + -8d) + d(7 + 2d)) = 0
(-28 + -8d + (7 * d + 2d * d)) = 0
(-28 + -8d + (7d + 2d2)) = 0

Combine like terms: -8d + 7d = -1d
(-28 + -1d + 2d2) = 0

Solving
-28 + -1d + 2d2 = 0

Solving for variable 'd'.

Factor a trinomial.
(-7 + -2d)(4 + -1d) = 0

Subproblem 1
Set the factor '(-7 + -2d)' equal to zero and attempt to solve:

Simplifying
-7 + -2d = 0

Solving
-7 + -2d = 0

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

Add '7' to each side of the equation.
-7 + 7 + -2d = 0 + 7

Combine like terms: -7 + 7 = 0
0 + -2d = 0 + 7
-2d = 0 + 7

Combine like terms: 0 + 7 = 7
-2d = 7

Divide each side by '-2'.
d = -3.5

Simplifying
d = -3.5
Subproblem 2
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
Solution
d = {-3.5, 4}