document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1136754>Question 1136754</A>: <I><SPAN STYLE=\"word-break: break-all;\"> determine if this quadrilateral with the given vertices is a square: A(1,-2), B(4,2), C(6,2), D(3,-2)  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #754554 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=754554\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> show that all sides are equal<BR>\n" );
document.write( "distance formula sqrt (difference in x s ^2+ difference in y s ^2)<BR>\n" );
document.write( "AB has distance 5 units (sqrt 25)<BR>\n" );
document.write( "BC and AD have distance 2 units<BR>\n" );
document.write( "The quadrilateral is not a square.\r<BR>\n" );
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document.write( "One may also use slopes to see if two opposite lines have the same slope and are perpendicular to the two other opposite lines.\r<BR>\n" );
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document.write( "Sketch a graph and plot a couple of points.  It is obvious the figure is not a square. </SPAN>\n" );
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