document.write( "Question 900323: A boat traveled downstream a distance of 52 mi and then came right back. If the speed of the current was 5 mph and the total trip took 4 hours and 20 minutes, find the average speed of the boat relative to the water. \n" ); document.write( "

Algebra.Com's Answer #545947 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi
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document.write( "52/(r+5) + 52/(r-5) = 13/3
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document.write( " 52(r-5) + 52(r+5) = 13/3(r^2 - 25)
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document.write( "  104r = (13/3)(r^2-25)
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document.write( "  13r^2 -312r - 13*25 = 0
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document.write( " r^2 - 24r - 25 = 0 
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document.write( "(r +1)(r-25) = 0,  r = 25mph
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