Respuesta :

DeanR

h(t) = 80t - 16t²

Ground level is h(0) = 0

We want to solve for t:

h(t)= 0

80t - 16t² = 0

16t(5 - t) = 0

t = 0 or t = 5

Answer: 5 seconds

Answer:5

Step-by-step explanation:Plug in numbers for t until you find an answer. 3 is too small. Plug in 4. Too small. Plug in 5. It works