Question

A pomegranate is thrown from ground level straight up into the air at time
t = 0 with velocity 96 feet per second. Its height at time t seconds is f(t) = −16t2 + 96t.
a) Find the time it hits the ground. t=? s
b) Find the time it reaches its highest point. t=?s
c) What is the maximum height? ____ft

I'm sorry, I do not understand how to even start with this problem. While we are given the starting velocity, how do you know what values to plug in for the rest of the unknowns?

Answer 1

f(t) = −16t^2 + 96t
when it hits the ground, f(t) = 0
-16t^2 + 96t = 0
t^2 - 6t=0
t(t-6) = 0
t = 0 , we knew that
or
t = 6

so it hits the ground after 6 seconds

b) find the vertex of f(t) = -16t^2 + 96t

c) see b)

Answer 2

How do you find the vertex? Do you just put it into a graphing calculator?

Answer 3

Wait nevermind! I got it! Thank you so much!