Question

Aubrey and Charlie are driving to a city that is 120 mi from their house. They have already traveled 20 mi, and they are driving at a constant rate of 50 mi/h. Complete the function that models the distance they drive as a function of time. Then complete a reasonable domain for this situation.
function notation in slope-intercept form: f(x) = ________
reasonable domain: ≤ x ≤

Answer 1

Answer:  The function that models the distance they drive is

f(x) = 50x + 20 where x is the time in hours

reasonable domain:  0 ≤ x ≤ 3

Step-by-step explanation:

examples:

95 = 50(1.5) + 20 After driving another hour and a half, they will have driven a total of 95 miles.

120 = 50(2) + 20  This means that after 2 more hours they will reach their destination.

There is a little ambiguity in the question. The function could be written as if they are starting out.  f(x) = 50t  

20 = 50(.4)  At 50 mph it took .4 hours to go 20 miles.

120 = 5(2.4)  The whole trip took 2.4 hours.