document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=99580>Question 99580</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If you add 100 to the number you get a perfect square.<BR>\n" );
document.write( "If you add 168 to that number you get another perfect square.<BR>\n" );
document.write( "What is that number? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #72532 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=72532\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> n=number ... n+100=a^2 ... n+268=b^2\r<BR>\n" );
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document.write( "b^2-a^2=168 ... (b-a)(b+a)=168\r<BR>\n" );
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document.write( "factors of 168 ... 1,168 ... 2,84 ... 3,56 ... 4,42 ... 6,28 ... 8,21 ... 12,14\r<BR>\n" );
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document.write( "sum of factors is 2b, so it must be even ... 4,42 gives b=23, a=19 ... 23^2-19^2=168\r<BR>\n" );
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document.write( "n+100=19^2 ... n=261 </SPAN>\n" );
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