5n^2+20n=60

Solution for 5n^2+20n=60 equation:

5n^2+20n=60

We move all terms to the left:

5n^2+20n-(60)=0

a = 5; b = 20; c = -60;
Δ = b2-4ac
Δ = 202-4·5·(-60)
Δ = 1600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1600}=40$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(20)-40}{2*5}=\frac{-60}{10}
=-6
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(20)+40}{2*5}=\frac{20}{10}
=2
$