28596+400x-10x^2=0

Solution for 28596+400x-10x^2=0 equation:

28596+400x-10x^2=0

a = -10; b = 400; c = +28596;
Δ = b2-4ac
Δ = 4002-4·(-10)·28596
Δ = 1303840
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:

$\sqrt{\Delta}=\sqrt{1303840}=\sqrt{16*81490}=\sqrt{16}*\sqrt{81490}=4\sqrt{81490}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(400)-4\sqrt{81490}}{2*-10}=\frac{-400-4\sqrt{81490}}{-20}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(400)+4\sqrt{81490}}{2*-10}=\frac{-400+4\sqrt{81490}}{-20}
$