0=5x^2-160x+1200

Solution for 0=5x^2-160x+1200 equation:

0=5x^2-160x+1200

We move all terms to the left:

0-(5x^2-160x+1200)=0

We add all the numbers together, and all the variables

-(5x^2-160x+1200)=0

We get rid of parentheses

-5x^2+160x-1200=0

a = -5; b = 160; c = -1200;
Δ = b2-4ac
Δ = 1602-4·(-5)·(-1200)
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{-(160)-40}{2*-5}=\frac{-200}{-10}
=+20
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(160)+40}{2*-5}=\frac{-120}{-10}
=+12
$