document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=742010>Question 742010</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If (a+b)^2 + (b+c)^2 + (c+d)^2 = 4(ab+bc+cd), prove a=b=c=d </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #452250 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=452250\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28a%2Bb%29%5E2+%2B+%28b%2Bc%29%5E2+%2B+%28c%2Bd%29%5E2+=+4%28ab%2Bbc%2Bcd%29 ALIGN=MIDDLE  ALT=\"%28a%2Bb%29%5E2+%2B+%28b%2Bc%29%5E2+%2B+%28c%2Bd%29%5E2+=+4%28ab%2Bbc%2Bcd%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so (a-b)^2=0<BR>\n" );
document.write( "a-b=0<BR>\n" );
document.write( "a=b\r<BR>\n" );
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document.write( "similarly b=c\r<BR>\n" );
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document.write( "c=d\r<BR>\n" );
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document.write( "a=b=c=d </SPAN>\n" );
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