document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=894909>Question 894909</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A motorist covers a distance of 210km. If his average velocity was 10km/h more, he would have completed the distance in half an hour less. \r<BR>\n" );
document.write( "\n" );
document.write( "Calculate his average speed.\r<BR>\n" );
document.write( "\n" );
document.write( "Thanks. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #542448 by </B><A HREF=/tutors/aboutme.mpl?userid=richwmiller><B>richwmiller(17219)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richwmiller><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=richwmiller><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=542448\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> r*t=d<BR>\n" );
document.write( "r*t=210<BR>\n" );
document.write( "(r+10)*(t-1/2)=210<BR>\n" );
document.write( "r*t=(r+10)*(t-1/2)<BR>\n" );
document.write( "rt+10t-r/2-5=210<BR>\n" );
document.write( "10t-r/2-5=0<BR>\n" );
document.write( "10*210/r-r/2-5=0<BR>\n" );
document.write( "2100/r-r/2-5=0<BR>\n" );
document.write( "4200-r^2-10r=0<BR>\n" );
document.write( "r^2+10r-4200=0<BR>\n" );
document.write( "(r-60)*(r+70)=0<BR>\n" );
document.write( "r=60 t=3.5 <BR>\n" );
document.write( "check<BR>\n" );
document.write( "60*3.5=210<BR>\n" );
document.write( "70*3=210<BR>\n" );
document.write( "ok\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );