0=20x^2-17x-63

Solution for 0=20x^2-17x-63 equation:

0=20x^2-17x-63

We move all terms to the left:

0-(20x^2-17x-63)=0

We add all the numbers together, and all the variables

-(20x^2-17x-63)=0

We get rid of parentheses

-20x^2+17x+63=0

a = -20; b = 17; c = +63;
Δ = b2-4ac
Δ = 172-4·(-20)·63
Δ = 5329
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5329}=73$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(17)-73}{2*-20}=\frac{-90}{-40}
=2+1/4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(17)+73}{2*-20}=\frac{56}{-40}
=-1+2/5
$