(4d-2)(-2d-5)=0

Solution for (4d-2)(-2d-5)=0 equation:

(4d-2)(-2d-5)=0

We multiply parentheses ..

(-8d^2-20d+4d+10)=0

We get rid of parentheses

-8d^2-20d+4d+10=0

We add all the numbers together, and all the variables

-8d^2-16d+10=0

a = -8; b = -16; c = +10;
Δ = b2-4ac
Δ = -162-4·(-8)·10
Δ = 576
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$d_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$d_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{576}=24$
$d_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-16)-24}{2*-8}=\frac{-8}{-16}
=1/2
$
$d_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-16)+24}{2*-8}=\frac{40}{-16}
=-2+1/2
$