document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=34979>Question 34979</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0395977258/algebrahomeworkh>Algebra and Trigonometry Structure and Method</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> A boat traveled 36 km downstream in 2h. the return trip upstream took 3 h. find the rate of the current. \r<BR>\n" );
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document.write( "i got d=rt <BR>\n" );
document.write( "downstream   72=(x+y)5<BR>\n" );
document.write( "upstream     72=(x-y)5<BR>\n" );
document.write( "then i solved for x and got 180 but when i tried for y everything cancels itself out, help please... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #21217 by </B><A HREF=/tutors/aboutme.mpl?userid=Paul><B>Paul(988)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Paul><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=21217\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let the speed of the boat be x<BR>\n" );
document.write( "Let the speed of the current be y<BR>\n" );
document.write( "Equation 1:<BR>\n" );
document.write( "2x+2y=36<BR>\n" );
document.write( "y=18-x (subsitution)<BR>\n" );
document.write( "3x-3y=36<BR>\n" );
document.write( "Subsitute for yL<BR>\n" );
document.write( "3x-3(18-x)=36<BR>\n" );
document.write( "6x=36+54<BR>\n" );
document.write( "x=15<BR>\n" );
document.write( "y=18-15<BR>\n" );
document.write( "y=3<BR>\n" );
document.write( "Hence, the speed of the boat is 15mph And the speed of the current is 3mph.<BR>\n" );
document.write( "Paul. </SPAN>\n" );
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