document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=50117>Question 50117</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have really been struggling with this chapter especialy section 5.6 Applications of Rational Expressions. I guess the story problems are wearing me down. could you please help me to see these in a better light? I tried setting it up however I know I am going about it wrong.\r<BR>\n" );
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document.write( "Sec 5.6  N 26<BR>\n" );
document.write( "Science and medicine. A plane flies 720 mi against a steady 30-mi/h head wind and then returns to the same point with the wind. If the entire trip takes 10 h, what is the plane’s speed in still air?<BR>\n" );
document.write( "(720/x+30)+ (720/x-30)=10<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #33314 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=33314\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A plane flies 720 mi against a steady 30-mi/h head wind and then returns to the same point with the wind. If the entire trip takes 10 h, what is the plane’s speed in still air?<BR>\n" );
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document.write( "With the wind DATA:<BR>\n" );
document.write( "distance = 720 mi ; rate = p+30 mph ; time = d/r= 720/(p+30)<BR>\n" );
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document.write( "Against the wind DATA:<BR>\n" );
document.write( "distance = 720 mi ; rate = p-30 mph ; time = d/r = 720/(p-30)<BR>\n" );
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document.write( "EQUATION:<BR>\n" );
document.write( "time + time = 10 hrs.<BR>\n" );
document.write( "720/(p+30) + 720/(p-30)= 10<BR>\n" );
document.write( "72/(p+30) + 72/(p-30)= 1<BR>\n" );
document.write( "72p+72p = p^2-900<BR>\n" );
document.write( "p^2-144p-900=0<BR>\n" );
document.write( "(p-150)(p+6)=0<BR>\n" );
document.write( "plane speed = 150 mph<BR>\n" );
document.write( "cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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