document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=133899>Question 133899</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Jennifer drives 400 miles at a certain speed to New York State for a ski vacation. When she returns home, the weather is bad and she drives 10 miles per hour slower and it takes her 2 hours longer. Find Jennifers speed on each part of the trip.\r<BR>\n" );
document.write( "\n" );
document.write( "HELP?!?!?! no idea </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #97920 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=97920\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Distance(d) equals Rate(r) times Time(t) or d=rt;  r=d/t and t=d/r\r<BR>\n" );
document.write( "\n" );
document.write( "Let r= her rate going to NY<BR>\n" );
document.write( "Then r-10=her rate returning in the bad wx<BR>\n" );
document.write( "Now we are told that her time coming back from NY is 2 hr longer than her time going, well:<BR>\n" );
document.write( "Her time going to NY=400/r<BR>\n" );
document.write( "Her time coming back=(400/(r-10)<BR>\n" );
document.write( "Now if we subtract her time going from her time coming back we should have 2 hr.<BR>\n" );
document.write( "So our equation to solve is:<BR>\n" );
document.write( " 400/(r-10) - 400/r=2  multiply each term by r(r-10)\r<BR>\n" );
document.write( "\n" );
document.write( "400r-400r+4000=2r(r-10) simplify and divide each term by 2\r<BR>\n" );
document.write( "\n" );
document.write( "2000=r^2-10r  subtract 2000 from each side\r<BR>\n" );
document.write( "\n" );
document.write( "r^2-10r-2000=2000-2000  collect like terms\r<BR>\n" );
document.write( "\n" );
document.write( "r^2-10r-2000=0  quadratic in standard form and it can be factored\r<BR>\n" );
document.write( "\n" );
document.write( "(r-50)(r+40)=0<BR>\n" );
document.write( "Neglect the negative value for r.  Rates in this problem are positive<BR>\n" );
document.write( " r=50 mph---------------------------------- her rate going to NY\r<BR>\n" );
document.write( "\n" );
document.write( "r-10=50-10=40 mph-----------------------her rate coming back from NY in the wx\r<BR>\n" );
document.write( "\n" );
document.write( "CK\r<BR>\n" );
document.write( "\n" );
document.write( "400/40 - 400/50=2<BR>\n" );
document.write( "10-8=2<BR>\n" );
document.write( "2=2\r<BR>\n" );
document.write( "\n" );
document.write( "Hope this helps---ptaylor<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );