SOLUTION: Melissa is driving to Philadelphia. Suppose that the remaining distance to drive (in miles) is a linear function of her driving time (in minutes). When graphed, the function gives

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Question 785266: Melissa is driving to Philadelphia. Suppose that the remaining distance to drive (in miles) is a linear function of her driving time (in minutes). When graphed, the function gives a line with a slope of -0.85 . See the figure below.
Melissa has 34 miles remaining after 43 minutes of driving. How many miles will be remaining after 51 minutes of driving?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
IF STUDYING EQUATION OF A LINE:
If d= distance (miles) to Philadelphia is a function of t = minutes driving, the equation for the function/loine is
d-34=-0.85%28t-43%29 (point-slope form of the equation for the line)
For t=43, d-34=0 <--> d=34
For t=51, d-34=-0.85%2851-43%29-->d-34=-0.85%2A8-->d-34=-6.8-->d=34-6.8-->d=highligh%2827.2%29
After 51 minutes of driving, Melissa will be highligh%2827.2%29 miles from Philadelphia.

FOR FIFTH GRADERS:
Melissa is driving 0.85 miles per minute, or 0.85%2A60mph=51mph).
In 8minutes=51minuts-43minutes of driving, Mellisa would travel
0.85%2A8miles=6.8miles,
so after 51 minutes of driving the distance remaining will be
34miles-6.8miles=27.2miles,
6.8miles less than the 34 miles remaining after 43 minutes of driving.