-25x^2+700x+500=0

Solution for -25x^2+700x+500=0 equation:

-25x^2+700x+500=0

a = -25; b = 700; c = +500;
Δ = b2-4ac
Δ = 7002-4·(-25)·500
Δ = 540000
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:

$\sqrt{\Delta}=\sqrt{540000}=\sqrt{90000*6}=\sqrt{90000}*\sqrt{6}=300\sqrt{6}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(700)-300\sqrt{6}}{2*-25}=\frac{-700-300\sqrt{6}}{-50}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(700)+300\sqrt{6}}{2*-25}=\frac{-700+300\sqrt{6}}{-50}
$