SOLUTION: Arthur is driving his car on a long road trip. On the highway he drives at an average speed of 90km/h. Through towns he drives at an average speed of 50km/h. So far he's been drivi

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Question 1050682: Arthur is driving his car on a long road trip. On the highway he drives at an average speed of 90km/h. Through towns he drives at an average speed of 50km/h. So far he's been driving for a total of 6 hours. Give a relation, d(c), which determines the total distance, d, Arthur has driven so far, given that he's driven through towns for c hours. And determine the domain and range of d(c).
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The distance he drives through towns is:
+50c+ km
The distance he drives on the highway is:
+90%2A%28+6+-+c+%29+
-------------------
+d%28c%29+=+50c+%2B+90%2A%28+6+-+c+%29+
+d%28c%29+=+50c+%2B+540+-+90c+
+d%28c%29+=+-40c+%2B+540+ km
--------------------------
The domain begins at +c+=+0+
and ends at +d%28c%29+=+0+
+0+=+-40c+%2B+540+
+40c+=+540+
+c+=+13.5+
0 < c < 13.5
--------------------
The range is
0 < d(c) < 540
--------------------
Here's the plot:
+graph%28+400%2C+400%2C+-5%2C+40%2C+-70%2C+700%2C+-40x+%2B+540+%29+