10n^2-80=-20n

Solution for 10n^2-80=-20n equation:

10n^2-80=-20n

We move all terms to the left:

10n^2-80-(-20n)=0

We get rid of parentheses

10n^2+20n-80=0

a = 10; b = 20; c = -80;
Δ = b2-4ac
Δ = 202-4·10·(-80)
Δ = 3600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3600}=60$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(20)-60}{2*10}=\frac{-80}{20}
=-4
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(20)+60}{2*10}=\frac{40}{20}
=2
$