200x-x2=9600

Solution for 200x-x2=9600 equation:

200x-x2=9600

We move all terms to the left:

200x-x2-(9600)=0

We add all the numbers together, and all the variables

-1x^2+200x-9600=0

a = -1; b = 200; c = -9600;
Δ = b2-4ac
Δ = 2002-4·(-1)·(-9600)
Δ = 1600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1600}=40$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(200)-40}{2*-1}=\frac{-240}{-2}
=+120
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(200)+40}{2*-1}=\frac{-160}{-2}
=+80
$