document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=473754>Question 473754</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boat travels 30 miles upstream and 30 miles downstream. The total time for both parts of the trip is 8 hours. the speed of the boat in still water is 8 mph. Find the speed of the current.\r<BR>\n" );
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document.write( "I have worked this problem 2 different ways and came up with 2 different answers both with radicals. \r<BR>\n" );
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document.write( "1. 30=(8+r)t  <~~ I solved this one for t=30/(8+r)<BR>\n" );
document.write( "   30=(8-r)t\r<BR>\n" );
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document.write( "   30=(8-r)(30/(8+r) the answer I got was 8+or- 2(squareroot of 15)\r<BR>\n" );
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document.write( "2. I used one from the website as a reference and worked it like this...<BR>\n" );
document.write( "    Current = X<BR>\n" );
document.write( "    upstream - x+8<BR>\n" );
document.write( "    downstream - 8-x<BR>\n" );
document.write( "30/(x+8)+30/(8-x)= 8<BR>\n" );
document.write( "LCM=(x+8)(8-x)<BR>\n" );
document.write( "the answer I got was 2(squareroot of 31)\r<BR>\n" );
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document.write( "Where am I going wrong!? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #324989 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=324989\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A boat travels 30 miles upstream and 30 miles downstream.<BR>\n" );
document.write( " The total time for both parts of the trip is 8 hours. the speed of the boat in still water is 8 mph.<BR>\n" );
document.write( " Find the speed of the current.<BR>\n" );
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document.write( "x = the speed of the current like you said<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(8+x) = speed downstream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(8-x) = speed upstream<BR>\n" );
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document.write( "Seems like you are on the right track here, let's just follow up this<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2F%288%2Bx%29 ALIGN=MIDDLE  ALT=\"30%2F%288%2Bx%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2F%288-x%29 ALIGN=MIDDLE  ALT=\"30%2F%288-x%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 8<BR>\n" );
document.write( "multiply by (8+x)(8-x), resulting in<BR>\n" );
document.write( "30(8-x) + 30(8+x) = 8(8-x)(8+x)<BR>\n" );
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document.write( "240 - 30x + 240 + 30x = 8(64 - x^2)<BR>\n" );
document.write( "480 = 512 - 8x^2<BR>\n" );
document.write( "8x^2 = 512 - 480<BR>\n" );
document.write( "8x^2 = 32<BR>\n" );
document.write( "divide by 8<BR>\n" );
document.write( "x^2 = 4<BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%284%29 ALIGN=MIDDLE  ALT=\"sqrt%284%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = 2 <BR>\n" );
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document.write( "Confirm this by finding the total times (upstr=6, downstr=10)<BR>\n" );
document.write( "30/10 + 30/6 =<BR>\n" );
document.write( "3 + 5 = 8 </SPAN>\n" );
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