0=320x-6000-x^2

Solution for 0=320x-6000-x^2 equation:

0=320x-6000-x^2

We move all terms to the left:

0-(320x-6000-x^2)=0

We add all the numbers together, and all the variables

-(320x-6000-x^2)=0

We get rid of parentheses

x^2-320x+6000=0

a = 1; b = -320; c = +6000;
Δ = b2-4ac
Δ = -3202-4·1·6000
Δ = 78400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{78400}=280$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-320)-280}{2*1}=\frac{40}{2}
=20
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-320)+280}{2*1}=\frac{600}{2}
=300
$