5d^2+21d=10d+35

Solution for 5d^2+21d=10d+35 equation:

5d^2+21d=10d+35

We move all terms to the left:

5d^2+21d-(10d+35)=0

We get rid of parentheses

5d^2+21d-10d-35=0

We add all the numbers together, and all the variables

5d^2+11d-35=0

a = 5; b = 11; c = -35;
Δ = b2-4ac
Δ = 112-4·5·(-35)
Δ = 821
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{-(11)-\sqrt{821}}{2*5}=\frac{-11-\sqrt{821}}{10}
$
$d_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(11)+\sqrt{821}}{2*5}=\frac{-11+\sqrt{821}}{10}
$