5d(2d-5)=2d+10

Solution for 5d(2d-5)=2d+10 equation:

5d(2d-5)=2d+10

We move all terms to the left:

5d(2d-5)-(2d+10)=0

We multiply parentheses

10d^2-25d-(2d+10)=0

We get rid of parentheses

10d^2-25d-2d-10=0

We add all the numbers together, and all the variables

10d^2-27d-10=0

a = 10; b = -27; c = -10;
Δ = b2-4ac
Δ = -272-4·10·(-10)
Δ = 1129
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$d_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$d_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$d_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-27)-\sqrt{1129}}{2*10}=\frac{27-\sqrt{1129}}{20}
$
$d_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-27)+\sqrt{1129}}{2*10}=\frac{27+\sqrt{1129}}{20}
$