Question 167746This question is from textbook Algebra 1
: A fishing trawler has radioed the Coast Guard for a helicopter to pick up an injured crew member. At the time of the emergency message, the trawler is 660 kilometers from the helicopter and heading toward it. The average speed of the trawler is 30 kilometers per hour, and the average speed of the helicopter is 300 kilometers per hour. How long will it take the helicopter to reach the trawler?
r*t=d
------------r---t--d
trawler-----30--t--30t
helicopter--300-t--300t
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Am I suppose to add like terms, or subtract them? I subtracted them.
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300t - 30t = 660
270t = 660
270t ÷ 270 = 660 ÷ 270
t = 2.44
2 hrs. 26 min.
This question is from textbook Algebra 1
Found 2 solutions by stanbon, jim_thompson5910:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! A fishing trawler has radioed the Coast Guard for a helicopter to pick up an injured crew member. At the time of the emergency message, the trawler is 660 kilometers from the helicopter and heading toward it. The average speed of the trawler is 30 kilometers per hour, and the average speed of the helicopter is 300 kilometers per hour. How long will it take the helicopter to reach the trawler?
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The closing speed of the two vehicles is 330 km/hr
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d/r = t
660/330 = 2 hrs.
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Cheers,
Stan H.
Answer by jim_thompson5910(35256) (Show Source):
You can put this solution on YOUR website! In this case, you add the terms. Why? Let's say that they are 10 miles apart and one travels 4 miles and the other travels 6 miles. If you add those two distances you get 10 miles. If you draw this on a number line, you'll find that the two will meet at the spot x=4.
So this means that the equation is 
Start with the given equation.
 Combine like terms on the left side.
 Divide both sides by  to isolate  .
 Reduce.
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Answer:
So the answer is which means that it takes 2 hours for the trawler and the helicopter to meet.
Now that we have our answer, let's check it
Since the trawler is going 30 km/hr, this means that the trawler covers a distance of  km. Also, since the helicopter travels 300 km/hr, the helicopter travels  km. Adding the two distances gives us  km which is the total distance.
Once again, if this is hard to grasp, draw a number line starting from 0 (the location of the trawler) and go by 30 until you get to 660 (the location of the helicopter). Since the trawler goes 60 km, this means that at location 60 the trawler meets the helicopter. From the viewpoint of the helicopter, the helicopter has to travel 600 km (to go from 660 to 60). These two distances add to 660 since they form parts of the whole number line that is drawn.
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