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| Question 891938:  At noon, a car left a gas station and traveled north at an average of r miles per hour. The car reached its destination t hours later. At 1:00 pm, a van left the same gas station and traveled south, Its average speed was 5 mph greater than the car's average speed. Write a polynomial expression (in two variables) that represents the total distance between the car and the van at the time that the car reached its destination.
 Answer by ankor@dixie-net.com(22740)
      (Show Source): 
You can put this solution on YOUR website! At noon, a car left a gas station and traveled north at an average of r miles per hour. The car reached its destination t hours later. rt = car dist
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 At 1:00 pm, a van left the same gas station and traveled south, Its average speed was 5 mph greater than the car's average speed.
 (r+5)(t-1) = van dist
 FOIL
 rt - r + 5t - 5 = van dist
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 Write a polynomial expression (in two variables) that represents the total distance between the car and the van at the time that the car reached its destination.
 d = rt + rt-r+5t-5
 d = 2rt - r + 5t - 5
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