document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=404644>Question 404644</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi I am in the need of some help on this word problem please. \r<BR>\n" );
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document.write( "To train for the running of a triathlon, jerri jogs 1 hour each day over the same 9 mile course. five miles of the course is downhill, whereas the other 4 miles is on level ground. jerri figures that she runs 2 miles per hour faster downhill than she runs on level ground. find the rate at which jerri runs on  level ground. My email address is wa_emily@yahoo.com\r<BR>\n" );
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document.write( "Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #286051 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=286051\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> jerri jogs 1 hour each day over the same 9 mile course.<BR>\n" );
document.write( " five miles of the course is downhill, whereas the other 4 miles is on level ground.<BR>\n" );
document.write( " jerri figures that she runs 2 miles per hour faster downhill than she runs on level ground.<BR>\n" );
document.write( " find the rate at which jerri runs on level ground. <BR>\n" );
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document.write( "Let s = the speed on level ground<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+2) = the speed down hill<BR>\n" );
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document.write( "Write a time equation: Time = dist/speed<BR>\n" );
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document.write( "Level ground time + downhill time = 1 hr<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2Fs ALIGN=MIDDLE  ALT=\"4%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F%28%28s%2B2%29%29 ALIGN=MIDDLE  ALT=\"5%2F%28%28s%2B2%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
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document.write( "Multiply by s(s+2) to clear the denominators, results:<BR>\n" );
document.write( "4(s+2) + 5s = s(s+2)<BR>\n" );
document.write( "4s + 8 + 5s = s^2 + 2s<BR>\n" );
document.write( "9s + 8 = s^2 + 2s<BR>\n" );
document.write( "Arrange as a quadratic equation on the right<BR>\n" );
document.write( "0 = s^2 + 2s - 9s - 8<BR>\n" );
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document.write( "s^2 - 7s - 8 = 0<BR>\n" );
document.write( "Factors to<BR>\n" );
document.write( "(s-8)(s+1) = 0<BR>\n" );
document.write( "The positive solution is all we want here<BR>\n" );
document.write( "s = 8 mph on level ground<BR>\n" );
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document.write( "Check solution by finding the actual times (downhill speed = 10 mph)<BR>\n" );
document.write( "4/8 + 5/10 =<BR>\n" );
document.write( "1/2 + 1/2 = 1 hr, confirms our solution of s = 8 </SPAN>\n" );
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