Answer:
The best estimate for the number of people in line at 9 a.m is 42.
Step-by-step explanation
Given x is number of people standing in line to catch a commuter train x hours after 5 a.m
Number of hours from 5 a.m to 9a.m= 4 hours.
Plugging x=4 in the given equation we have:
[tex]y=-5.1314^{2} +31.821(4)-3.333[/tex]
Or ,
y=-5.1314(16)+127.284-3.333
y=-82.1024 +127.284-3.333
y=41.84
Or y=42 .