document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=898767>Question 898767</A>: <I><SPAN STYLE=\"word-break: break-all;\"> You and your friend part at an intersection. You drive off north at a constant speed, and your friend drives east at a speed that is 9 mph higher. After 3 hours the distance between you and your friend is 282.78 miles. You have been driving at _______ mph. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #545015 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=545015\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You and your friend part at an intersection.<BR>\n" );
document.write( " You drive off north at a constant speed, and your friend drives east at a speed that is 9 mph higher.<BR>\n" );
document.write( " After 3 hours the distance between you and your friend is 282.78 miles.<BR>\n" );
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document.write( "let s = your driving speed<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+9) = your friend's<BR>\n" );
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document.write( "In 3 hrs: <BR>\n" );
document.write( "3s = your driving dist<BR>\n" );
document.write( "(3(s+9) = your friend's dist<BR>\n" );
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document.write( "this is a rt triangle problem, a^2 + b^2 = c^2, where<BR>\n" );
document.write( "a = 3s<BR>\n" );
document.write( "b = 3(s+9)<BR>\n" );
document.write( "c = 282.78<BR>\n" );
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document.write( "(3s)^2 + (3(s+9))^2 = 282.78^2<BR>\n" );
document.write( "9s^2 + (3s+27)^2 = 79964.53<BR>\n" );
document.write( "9s^2 + 9s^2 + 81s + 81s + 729 - 79964.53 = 0<BR>\n" );
document.write( "18s^2 + 162s - 79235.53 = 0<BR>\n" );
document.write( "Using the quadratic formula, I got:<BR>\n" );
document.write( "s = 62 mph is your speed<BR>\n" );
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document.write( "Check this on your calc:<BR>\n" );
document.write( "3*62 = 186 mi<BR>\n" );
document.write( "3*71 = 213 mi<BR>\n" );
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document.write( " You have been driving at _______ mph. </SPAN>\n" );
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