-25x^2+200x+300=0

Solution for -25x^2+200x+300=0 equation:

-25x^2+200x+300=0

a = -25; b = 200; c = +300;
Δ = b2-4ac
Δ = 2002-4·(-25)·300
Δ = 70000
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:

$\sqrt{\Delta}=\sqrt{70000}=\sqrt{10000*7}=\sqrt{10000}*\sqrt{7}=100\sqrt{7}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(200)-100\sqrt{7}}{2*-25}=\frac{-200-100\sqrt{7}}{-50}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(200)+100\sqrt{7}}{2*-25}=\frac{-200+100\sqrt{7}}{-50}
$