Question

50 POINTS!!!!! HELP PLEASE!!! HELP IS NEEDED!!!!!!!!!

A train is traveling 55 miles per hour to a destination that is 330 miles away. The function f(x)=−55x+330 represents the remaining number of miles to the destination after x hours of travel.

What is the practical domain of the function f?

all real numbers from 0 to 6
all multiples of 55 between 0 and 330
all whole numbers from 0 to 6
all real numbers from 0 to 330

Answer 1

the domain is the numbers that would satisfy x

since x = the number of hours

it would be all real numbers between 0 and 6

Explanation:

Answer 2

You need to drive 6 hours
If you start at 11PM, you'll get to the destination at 5 AM
Using , we get . Solve for 't' to get . So it takes 6 hours which means that you'll arrive at 11 pm + 6 hours = 5 am
The fact that you start at 11pm is not important.


D = rt

330 = 55t

330/55 = t

6 = t

Assuming that you make no stops, it will take you 6 hours to make the trip if

you keep the same rate per hour.

If starting at 11pm, you will arrive at 5am.