-15x^2+360x-1800=0

Solution for -15x^2+360x-1800=0 equation:

-15x^2+360x-1800=0

a = -15; b = 360; c = -1800;
Δ = b2-4ac
Δ = 3602-4·(-15)·(-1800)
Δ = 21600
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:

$\sqrt{\Delta}=\sqrt{21600}=\sqrt{3600*6}=\sqrt{3600}*\sqrt{6}=60\sqrt{6}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(360)-60\sqrt{6}}{2*-15}=\frac{-360-60\sqrt{6}}{-30}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(360)+60\sqrt{6}}{2*-15}=\frac{-360+60\sqrt{6}}{-30}
$