SOLUTION: The question is: Two cars start at the same point and travel in opposite directions. One car travels 5 mph faster than the other car. After 4 hrs, the two cars are 420 mile
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Question 266105: The question is: Two cars start at the same point and travel in opposite directions. One car travels 5 mph faster than the other car. After 4 hrs, the two cars are 420 miles apart. Find the speed of each car.
One set of equations I tried was x+y=4, 5x+y=420, and another set was x+y=420, 5x+4y=420. I was unable to get the correct answers with either set of equations. Thanks for your help!! Found 2 solutions by Alan3354, josmiceli:Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! Two cars start at the same point and travel in opposite directions. One car travels 5 mph faster than the other car. After 4 hrs, the two cars are 420 miles apart. Find the speed of each car.
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Their combined speed is 420/4 = 105 mph
x + y = 105 (combined)
x - y = 5 (difference)
-------------------------- Add
2x = 110
x = 55
Speeds = 55 and 50
You can put this solution on YOUR website! By far, the easiest way to solve this is to just visualize it
and don't think of it as 2 cars, but 1 car which is going at
the combined speed of both cars. You don't care where that 1
car starts from. All you care about is that it goes mi
in hrs. Call the speed , the combined speed.
The equation would be: mi/hr mi/hr
The faster car goes 55 mi/hr and
the slower car goes 50 mi/hr
check answers: mi mi
OK
