8x^2+14x-64=0

Solution for 8x^2+14x-64=0 equation:

8x^2+14x-64=0

a = 8; b = 14; c = -64;
Δ = b2-4ac
Δ = 142-4·8·(-64)
Δ = 2244
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:

$\sqrt{\Delta}=\sqrt{2244}=\sqrt{4*561}=\sqrt{4}*\sqrt{561}=2\sqrt{561}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(14)-2\sqrt{561}}{2*8}=\frac{-14-2\sqrt{561}}{16}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(14)+2\sqrt{561}}{2*8}=\frac{-14+2\sqrt{561}}{16}
$