document.write( "Question 442909: The current in a stream moves at a speed of 4mi/h. A boat travels 4 mi upstream and 12 mi downstream in a total time of 2 hours. What is the speed of the boat in still water? \n" ); document.write( "
Algebra.Com's Answer #308204 by jorel1380(3719)\"\" \"About 
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4/x-4+12/x+4=2
\n" ); document.write( "4(x+4)+12(x-4)=2x2-32
\n" ); document.write( "4x+16+12x-48=2x2-32
\n" ); document.write( "0=2x2-16x
\n" ); document.write( "x2=8x
\n" ); document.write( "x=8
\n" ); document.write( "The speed of the boat in still water is 8mph..
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