Answer:
The ball takes 5 seconds to hit the ground
Step-by-step explanation:
The equation to model the height of a golf ball in time t is:
[tex]h(t)=80t-16t^2[/tex]
There are two moments when the height is zero: At launch time and when it hits the ground. To find the last time, we equate:
[tex]80t-16t^2=0[/tex]
Factoring out t:
[tex]t(80-16t)=0[/tex]
It gives us two solutions:
t=0
[tex]80-16t=0[/tex]
Solving:
[tex]-16t=-80[/tex]
[tex]t=-80/(-16)=5[/tex]
t = 5 sec
Thus, the ball takes 5 seconds to hit the ground
