n(4n-1)-5=0

Solution for n(4n-1)-5=0 equation:

n(4n-1)-5=0

We multiply parentheses

4n^2-1n-5=0

a = 4; b = -1; c = -5;
Δ = b2-4ac
Δ = -12-4·4·(-5)
Δ = 81
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{81}=9$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-9}{2*4}=\frac{-8}{8}
=-1
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+9}{2*4}=\frac{10}{8}
=1+1/4
$