1536=-16t^2+320t

Solution for 1536=-16t^2+320t equation:

1536=-16t^2+320t

We move all terms to the left:

1536-(-16t^2+320t)=0

We get rid of parentheses

16t^2-320t+1536=0

a = 16; b = -320; c = +1536;
Δ = b2-4ac
Δ = -3202-4·16·1536
Δ = 4096
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4096}=64$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-320)-64}{2*16}=\frac{256}{32}
=8
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-320)+64}{2*16}=\frac{384}{32}
=12
$