document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=209061>Question 209061</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Determine whether the points lie on a straight line<BR>\n" );
document.write( "A(5, 1, 3), B(7, 9, -1), C(1, -15, 11) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #158403 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=158403\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Determine whether the points lie on a straight line<BR>\n" );
document.write( "A(5,1,3), B(7,9,-1), C(1,-15,11)<BR>\n" );
document.write( "-----------<BR>\n" );
document.write( "For A to B:<BR>\n" );
document.write( "diffx = 2<BR>\n" );
document.write( "diffy = 8<BR>\n" );
document.write( "diffz = -4<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "For A to C:<BR>\n" );
document.write( "diffx = -4<BR>\n" );
document.write( "diffy = -16<BR>\n" );
document.write( "diffz = 8<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "The differences have the same ratios, ie, the AC differences are -2 times the AB differences.  The 3 points are colinear. </SPAN>\n" );
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