-16x^2+64x+320=0

Solution for -16x^2+64x+320=0 equation:

-16x^2+64x+320=0

a = -16; b = 64; c = +320;
Δ = b2-4ac
Δ = 642-4·(-16)·320
Δ = 24576
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:

$\sqrt{\Delta}=\sqrt{24576}=\sqrt{4096*6}=\sqrt{4096}*\sqrt{6}=64\sqrt{6}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(64)-64\sqrt{6}}{2*-16}=\frac{-64-64\sqrt{6}}{-32}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(64)+64\sqrt{6}}{2*-16}=\frac{-64+64\sqrt{6}}{-32}
$