x^2-8x-115=0

Solution for x^2-8x-115=0 equation:

x^2-8x-115=0

a = 1; b = -8; c = -115;
Δ = b2-4ac
Δ = -82-4·1·(-115)
Δ = 524
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:

$\sqrt{\Delta}=\sqrt{524}=\sqrt{4*131}=\sqrt{4}*\sqrt{131}=2\sqrt{131}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-8)-2\sqrt{131}}{2*1}=\frac{8-2\sqrt{131}}{2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-8)+2\sqrt{131}}{2*1}=\frac{8+2\sqrt{131}}{2}
$