document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=162164>Question 162164</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0131889680/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> A motorboat heads upstream on a river that has a current of 3 miles per hour. the trip upstream takes 5 hours, and the return trip takes 2.5 hours. what is the speed of the motorboat? (assume that the motorboat maintains a constant speed relative to the water) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #119546 by </B><A HREF=/tutors/aboutme.mpl?userid=KnightOwlTutor><B>KnightOwlTutor(293)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KnightOwlTutor><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=KnightOwlTutor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=119546\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> When you are traveling upstream you are going against the current so you have to overcome the speed of the current which will slow you down.\r<BR>\n" );
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document.write( "Rate of motorboat upstream is x-3\r<BR>\n" );
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document.write( "When you are traveling downstream the current contributes to your speed\r<BR>\n" );
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document.write( "Rate of motorboat downstream x+3\r<BR>\n" );
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document.write( "Distance traveled is the same\r<BR>\n" );
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document.write( "(x-3)5=(x+3)(2.5)\r<BR>\n" );
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document.write( "5x-15=2.5x+7.5\r<BR>\n" );
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document.write( "add 15 to both sides \r<BR>\n" );
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document.write( "5x=2.5x +22.5\r<BR>\n" );
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document.write( "Subtract 2.5x from both sides\r<BR>\n" );
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document.write( "2.5x=22.5\r<BR>\n" );
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document.write( "Divide both sides by 2.5\r<BR>\n" );
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document.write( "x=9 miles per hour\r<BR>\n" );
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document.write( "Let's double check\r<BR>\n" );
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document.write( "(9-3)*5=30 \r<BR>\n" );
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document.write( "12*2.5=30  </SPAN>\n" );
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