0=4x^2-x-5

Solution for 0=4x^2-x-5 equation:

0=4x^2-x-5

We move all terms to the left:

0-(4x^2-x-5)=0

We add all the numbers together, and all the variables

-(4x^2-x-5)=0

We get rid of parentheses

-4x^2+x+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:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

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