-16t^2+64t+260=0

Solution for -16t^2+64t+260=0 equation:

-16t^2+64t+260=0

a = -16; b = 64; c = +260;
Δ = b2-4ac
Δ = 642-4·(-16)·260
Δ = 20736
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{20736}=144$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(64)-144}{2*-16}=\frac{-208}{-32}
=6+1/2
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(64)+144}{2*-16}=\frac{80}{-32}
=-2+1/2
$