document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=514833>Question 514833</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A trip involves 15 miles on a dirt trail and 90 miles on a freeway. The velocity for the freeway portion was 30 mph more than the velocity for the dirt trail portion. The entire trip took 2 hours. What was the velocity, in miles per hour, for each part of the trip? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #343784 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=343784\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A trip involves 15 miles on a dirt trail and 90 miles on a freeway.<BR>\n" );
document.write( " The velocity for the freeway portion was 30 mph more than the velocity for the dirt trail portion.<BR>\n" );
document.write( " The entire trip took 2 hours. <BR>\n" );
document.write( "What was the velocity, in miles per hour, for each part of the trip?<BR>\n" );
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document.write( "Let s = speed on dirt<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+30) = speed on freeway<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write a time equation; time = dist/speed<BR>\n" );
document.write( ":<BR>\n" );
document.write( "dirt time + freeway time = 2 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15%2Fs ALIGN=MIDDLE  ALT=\"15%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=90%2F%28%28s%2B30%29%29 ALIGN=MIDDLE  ALT=\"90%2F%28%28s%2B30%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 2<BR>\n" );
document.write( "multiply by s(s+30), results:<BR>\n" );
document.write( "15(s+30) + 90s = 2s(s+30)<BR>\n" );
document.write( "15s + 450 + 90s = 2s^2 + 60s<BR>\n" );
document.write( "105s + 450 = 2s^2 + 60s<BR>\n" );
document.write( "0 = 2s^2 + 60s - 105s - 450<BR>\n" );
document.write( "A quadratic equation<BR>\n" );
document.write( "2s^2 - 45s - 450 = 0<BR>\n" );
document.write( "Factors to:<BR>\n" );
document.write( "(2s + 15)(s - 30) = 0<BR>\n" );
document.write( "The positive solution<BR>\n" );
document.write( "s = 30 mph on dirt<BR>\n" );
document.write( "then<BR>\n" );
document.write( "30+30 = 60 mph on the freeway<BR>\n" );
document.write( ":<BR>\n" );
document.write( ":<BR>\n" );
document.write( "You can check this by finding the actual time at each speed </SPAN>\n" );
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