5n^2-1n-1980=0

Solution for 5n^2-1n-1980=0 equation:

5n^2-1n-1980=0

a = 5; b = -1; c = -1980;
Δ = b2-4ac
Δ = -12-4·5·(-1980)
Δ = 39601
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{39601}=199$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-199}{2*5}=\frac{-198}{10}
=-19+4/5
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+199}{2*5}=\frac{200}{10}
=20
$