Question

The height in feet of the projectile seconds after lunch is modeled by the equation h=32t - 16t2 how long after launch does the projectile return to the ground

Answer 1

When h=0 is when it returns to the ground
solve

0=32t-16t^2
factor
0=16t(2-t)
set equal to zero

0=16t
0=t

0=2-t
t=2

at t=0 and 2
it returns after 2 seconds