-8x2-236x+364=0

Solution for -8x2-236x+364=0 equation:

-8x^2-236x+364=0

a = -8; b = -236; c = +364;
Δ = b2-4ac
Δ = -2362-4·(-8)·364
Δ = 67344
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:

$\sqrt{\Delta}=\sqrt{67344}=\sqrt{16*4209}=\sqrt{16}*\sqrt{4209}=4\sqrt{4209}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-236)-4\sqrt{4209}}{2*-8}=\frac{236-4\sqrt{4209}}{-16}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-236)+4\sqrt{4209}}{2*-8}=\frac{236+4\sqrt{4209}}{-16}
$