document.write( "Question 902945: A boy rows a boat against a stream flowing at 2 kmph for a distance of 9 km,and then turns round and rows back with the current. If the whole trip occupies 6 hours, find the boys rowing speed in still water. \n" ); document.write( "
Algebra.Com's Answer #547611 by lwsshak3(11628)\"\" \"About 
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A boy rows a boat against a stream flowing at 2 kmph for a distance of 9 km,and then turns round and rows back with the current. If the whole trip occupies 6 hours, find the boys rowing speed in still water.
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\n" ); document.write( "let x=speed of boat in still water
\n" ); document.write( "x+2=speed of boat downstream
\n" ); document.write( "x-2=speed of boat upstream
\n" ); document.write( "travel time=distance/speed
\n" ); document.write( "9/(x+2)+9/(x-2)=6
\n" ); document.write( "lcd:(x+2)(x-2)
\n" ); document.write( "9(x-2)+9(x+2)=6(x^2-4)
\n" ); document.write( "9x-18+9x+18=6x^2-24
\n" ); document.write( "6x^2-18x-24=0
\n" ); document.write( "x^2-3x-4=0
\n" ); document.write( "(x-4)(x+1)=0
\n" ); document.write( "x=4
\n" ); document.write( "Boys rowing speed in still water=4 kmph
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