8x^2+14x-85=0

Solution for 8x^2+14x-85=0 equation:

8x^2+14x-85=0

a = 8; b = 14; c = -85;
Δ = b2-4ac
Δ = 142-4·8·(-85)
Δ = 2916
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2916}=54$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(14)-54}{2*8}=\frac{-68}{16}
=-4+1/4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(14)+54}{2*8}=\frac{40}{16}
=2+1/2
$