20x^2-600x+1500=0

Solution for 20x^2-600x+1500=0 equation:

20x^2-600x+1500=0

a = 20; b = -600; c = +1500;
Δ = b2-4ac
Δ = -6002-4·20·1500
Δ = 240000
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:

$\sqrt{\Delta}=\sqrt{240000}=\sqrt{40000*6}=\sqrt{40000}*\sqrt{6}=200\sqrt{6}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-600)-200\sqrt{6}}{2*20}=\frac{600-200\sqrt{6}}{40}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-600)+200\sqrt{6}}{2*20}=\frac{600+200\sqrt{6}}{40}
$