document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=90968>Question 90968</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If I am given three points and ask to find a fourth so that they are vertices of a parallelogram, how do I find the fourth? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #66031 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=66031\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If I am given three points and ask to find a fourth so that they are vertices of a parallelogram, how do I find the fourth?<BR>\n" );
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document.write( "Plot the three points so you can see what you are doing.<BR>\n" );
document.write( "The three points will determine two sides of the parallelogram<BR>\n" );
document.write( "if you choose the proper pair of points for each line.<BR>\n" );
document.write( "Now you should see approximately where the 4th point has to be<BR>\n" );
document.write( "You need to find the equation of two lines; each of the lines<BR>\n" );
document.write( "is parallel to one of the original sides and passes thru the<BR>\n" );
document.write( "proper known point.<BR>\n" );
document.write( "Once you get those two equations you need to find the intersection<BR>\n" );
document.write( "of those two lines to determine the 4th vertex of the parallelogram.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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