document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=88265>Question 88265</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Is the following trinomial a perfect square? Explain why or why not.\r<BR>\n" );
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document.write( "x^2 – 18x + 81\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #64103 by </B><A HREF=/tutors/aboutme.mpl?userid=rapaljer><B>rapaljer(4671)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rapaljer><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=rapaljer><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=64103\">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=x%5E2+-+18x+%2B+81 ALIGN=MIDDLE  ALT=\"x%5E2+-+18x+%2B+81\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-9%29%5E2 ALIGN=MIDDLE  ALT=\"%28x-9%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Yes!  It is a perfect square trinomial essentially because the x^2 coefficient is 1, and if you take HALF of the middle term and SQUARE the result, you get the last term which is 81.  In other words, if you take half of -18, you get -9, then if you square the (-9) you get 81, which is the last term of the trinomial.  Therefore, it IS a perfect square trinomial!!\r<BR>\n" );
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document.write( "R^2 </SPAN>\n" );
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