8x^2-38x-780=0

Solution for 8x^2-38x-780=0 equation:

8x^2-38x-780=0

a = 8; b = -38; c = -780;
Δ = b2-4ac
Δ = -382-4·8·(-780)
Δ = 26404
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:

$\sqrt{\Delta}=\sqrt{26404}=\sqrt{4*6601}=\sqrt{4}*\sqrt{6601}=2\sqrt{6601}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-38)-2\sqrt{6601}}{2*8}=\frac{38-2\sqrt{6601}}{16}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-38)+2\sqrt{6601}}{2*8}=\frac{38+2\sqrt{6601}}{16}
$