document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=37237>Question 37237</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0072549017/algebrahomeworkh>Beginning Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> 26. Science and medicine. A plane flies 720 mi against a steady 30-mi/headwind and then returns to the same point with the wind. If the entire trip takes 10h, what is the plane’s speed in still air?\r<BR>\n" );
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document.write( "I think the problem should be stated like this but I'm not sure. I just can't seem to get it to work.<BR>\n" );
document.write( "(720/x-20)+(720/x+20)=12 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #22917 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=22917\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Where did you get 12 and 20 from?<BR>\n" );
document.write( "Since the entire time for the trip is 10h, it is going to be SPEED 1 + SPEED 2.<BR>\n" );
document.write( "EQUATION:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=720%2F%28x-30%29%2B720%2F%28x%2B30%29=10 ALIGN=MIDDLE  ALT=\"720%2F%28x-30%29%2B720%2F%28x%2B30%29=10\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "720[(x+30)+(x-30)]=10[(x+30)(x-30)]<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=720%282x%29=10%28x%5E2-900%29 ALIGN=MIDDLE  ALT=\"720%282x%29=10%28x%5E2-900%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1440x=10x%5E2-9000 ALIGN=MIDDLE  ALT=\"1440x=10x%5E2-9000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2-144x-900=0 ALIGN=MIDDLE  ALT=\"x%5E2-144x-900=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+%28-%28-144%29+%2B-+sqrt%28+%28-144%29%5E2-4%2A1%2A%28-900%29+%29%29%2F%282%2A1%29+ ALIGN=MIDDLE  ALT=\"x+=+%28-%28-144%29+%2B-+sqrt%28+%28-144%29%5E2-4%2A1%2A%28-900%29+%29%29%2F%282%2A1%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "x=150<BR>\n" );
document.write( "Hence, the speed of the plane is 150mph.<BR>\n" );
document.write( " </SPAN>\n" );
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