document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=699652>Question 699652</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me! I need to solve this word problem using the eliminating method.\r<BR>\n" );
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document.write( "A steamboaat went 8 miles upstream in 1 hour. The return trip took only 30 minuts. Assume that the speed of the current and the direction were constant during both parts of the trip. Find the speed of the boat in still water and the speed of the current. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #431566 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=431566\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A steamboat went 8 miles upstream in 1 hour.<BR>\n" );
document.write( " The return trip took only 30 minutes.<BR>\n" );
document.write( " Assume that the speed of the current and the direction were constant during both parts of the trip.<BR>\n" );
document.write( " Find the speed of the boat in still water and the speed of the current.<BR>\n" );
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document.write( "Let s = the boat speed in still water<BR>\n" );
document.write( "Let c = the rate of the current<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s-c) = effective speed upstream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(s+c) = effective speed downstream<BR>\n" );
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document.write( "Change 30 min to .5 hr<BR>\n" );
document.write( "Write a distance equation for each way, dist = time * speed<BR>\n" );
document.write( " 1(s-c) = 8<BR>\n" );
document.write( ".5(s+c) = 8<BR>\n" );
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document.write( "The 1st equation we can ignore the 1, <BR>\n" );
document.write( "the second equation divide both sides by .5<BR>\n" );
document.write( "s - c = 8<BR>\n" );
document.write( "s + c = 16<BR>\n" );
document.write( "--------------adding eliminates c, find s<BR>\n" );
document.write( "2s = 24<BR>\n" );
document.write( "s = 12 mph in still water<BR>\n" );
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document.write( "find c<BR>\n" );
document.write( "12 + c = 16<BR>\n" );
document.write( "c = 16-12<BR>\n" );
document.write( "c = 4 mph is the current<BR>\n" );
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document.write( "Check this<BR>\n" );
document.write( "1(12 - 4) = 8<BR>\n" );
document.write( "and<BR>\n" );
document.write( ".5(12 + 4) = 8 </SPAN>\n" );
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