Answer:
Explanation:
Recall that distance = (rate)(time). Here the rate is 30 mph and the time 3.5 hr. The distance traveled is proportional to the time passing by. The graph of the distance function is a straight line with slope equal to the "rate" named above:
d(x) = (30 mph)x
Since x (elapsed time) can't be negative in this situation, we write the domain as 0 ≤ x ≤ 3.5 hr.