-5n^2=-220

Solution for -5n^2=-220 equation:

-5n^2=-220

We move all terms to the left:

-5n^2-(-220)=0

We add all the numbers together, and all the variables

-5n^2+220=0

a = -5; b = 0; c = +220;
Δ = b2-4ac
Δ = 02-4·(-5)·220
Δ = 4400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{4400}=\sqrt{400*11}=\sqrt{400}*\sqrt{11}=20\sqrt{11}$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-20\sqrt{11}}{2*-5}=\frac{0-20\sqrt{11}}{-10}
=-\frac{20\sqrt{11}}{-10}
=-\frac{2\sqrt{11}}{-1}
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+20\sqrt{11}}{2*-5}=\frac{0+20\sqrt{11}}{-10}
=\frac{20\sqrt{11}}{-10}
=\frac{2\sqrt{11}}{-1}
$