Answer:
D=160-13 1/3t
Step-by-step explanation:
D is distance in this instance
We are using y=mx+b for this.
The initial distance is 160 miles, that's our y-intercept or b.
Now we need to find our slope. If Andrew is 40 miles away in 3 hours, he is 13 and 1/3 miles away in 1 hour. It's negative because you are subtracting from the initial distance. You can keep that as an improper fraction if that makes it easier for you.
Now plug it in
Distance=13 1/3 miles times how many hours subtracted from 160 or D=-13 1/3+160. This can be rearranged to the answer above.