document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=67919>Question 67919</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0395430526/algebrahomeworkh>Algebra:Structure and Method</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> If I increase my usual driving speed by 10 km/h, I can drive the 255 km to Nashviille in 24 minutes less than usual. How fast do I usually drive? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #48307 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley71><B>checkley71(8403)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley71><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=48307\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 255/x=255/(x+10)+.4<BR>\n" );
document.write( "255/x=(255+.4x+4)/(x+10)<BR>\n" );
document.write( "255/x=(259+.4x)/(x=10)<BR>\n" );
document.write( "255(x+100=x(259+.4x)/(x+10)<BR>\n" );
document.write( "255x+2550=259x+.4x^2<BR>\n" );
document.write( ".4x^2+4x-2550=0<BR>\n" );
document.write( "(.4x-30)(x+85)=0<BR>\n" );
document.write( ".4x-30=0<BR>\n" );
document.write( ".4x=30<BR>\n" );
document.write( "x=30/.4<BR>\n" );
document.write( "x=75 km/h is the normal speed<BR>\n" );
document.write( "75+10=85 km/h is the faster trip speed<BR>\n" );
document.write( "proof<BR>\n" );
document.write( "255/75=255/85+.4<BR>\n" );
document.write( "3.4+3+.4<BR>\n" );
document.write( "3.4=3.4\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );