0=x^2-300x-20000

Solution for 0=x^2-300x-20000 equation:

0=x^2-300x-20000

We move all terms to the left:

0-(x^2-300x-20000)=0

We add all the numbers together, and all the variables

-(x^2-300x-20000)=0

We get rid of parentheses

-x^2+300x+20000=0

We add all the numbers together, and all the variables

-1x^2+300x+20000=0

a = -1; b = 300; c = +20000;
Δ = b2-4ac
Δ = 3002-4·(-1)·20000
Δ = 170000
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{170000}=\sqrt{10000*17}=\sqrt{10000}*\sqrt{17}=100\sqrt{17}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(300)-100\sqrt{17}}{2*-1}=\frac{-300-100\sqrt{17}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(300)+100\sqrt{17}}{2*-1}=\frac{-300+100\sqrt{17}}{-2}
$