0=12x^2-400x+2400

Solution for 0=12x^2-400x+2400 equation:

0=12x^2-400x+2400

We move all terms to the left:

0-(12x^2-400x+2400)=0

We add all the numbers together, and all the variables

-(12x^2-400x+2400)=0

We get rid of parentheses

-12x^2+400x-2400=0

a = -12; b = 400; c = -2400;
Δ = b2-4ac
Δ = 4002-4·(-12)·(-2400)
Δ = 44800
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:

$\sqrt{\Delta}=\sqrt{44800}=\sqrt{6400*7}=\sqrt{6400}*\sqrt{7}=80\sqrt{7}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(400)-80\sqrt{7}}{2*-12}=\frac{-400-80\sqrt{7}}{-24}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(400)+80\sqrt{7}}{2*-12}=\frac{-400+80\sqrt{7}}{-24}
$