## Oliver is going to drive from his house to City A without stopping. Oliver plans to drive at a speed of 40 miles per hour, and after

Question

Oliver is going to drive from his house to City A without stopping. Oliver plans to drive at a speed of 40 miles per hour, and after driving for 3 hours, he will be 80 miles away from City A. Write an equation for the function
D
(
t
)
,
D(t), representing Oliver’s distance from City A
t
t hours after leaving his house.

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2 weeks 2021-09-10T11:59:37+00:00 2 Answers 0

D(t) = 200 – 40t

Step-by-step explanation:

Oliver lives some distance m away from city A. We know as he drives, he will get closer to city A, so his distance should decrease. so we are expecting a negative coefficient for t, let’s call it r.

so we have D(t) = m – rt

we know he is driving at 40 mph, so r=40

D(t) = m – 40t

we know that after driving for 3 hours, he is 80 miles from city A.

D(3) = 80 = m – 40*3

80 = m – 120

200 = m

and so we have our equation!

D(t) = 200 – 40t