document.write( "Question 513157: Meg rowed her boat upstream a distance of 39 mi and then rowed back to the starting point. The total time of the trip was 16 hours. If the rate of the current was 5 mph, find the average speed of the boat relative to the water.\r
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\n" ); document.write( "\n" ); document.write( "***I need it worked out in detail please and thank you \n" ); document.write( "
Algebra.Com's Answer #342889 by stanbon(75887)\"\" \"About 
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Meg rowed her boat upstream a distance of 39 mi and then rowed back to the starting point. The total time of the trip was 16 hours. If the rate of the current was 5 mph, find the average speed of the boat relative to the water. \r
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\n" ); document.write( "Upstream DATA:
\n" ); document.write( "distance = 39 miles ; rate = b-5 mph ; time = d/r = 39/(b-5) hrs
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\n" ); document.write( "Downstream DATA:
\n" ); document.write( "distance = 39 miles ; rate = b+5 mph ; time = d/r = 39/(b+5) hrs
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\n" ); document.write( "Equation:
\n" ); document.write( "time + time = 16 hrs
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\n" ); document.write( "39/(b-5) + 39/(b+5) = 16
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\n" ); document.write( "1/(b-5) + 1/(b+5) = 16/39
\n" ); document.write( "[b+5+b-5]/b^2-25 = 16/39
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\n" ); document.write( "39*2b = 16b^2-400
\n" ); document.write( "39b = 8b^2-200
\n" ); document.write( "8b^2-39b-200 = 0
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\n" ); document.write( "Positive solution:
\n" ); document.write( "b = 8 mph (speed of the boat relative to the water)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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