document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1208181>Question 1208181</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the missing number\r<BR>\n" );
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document.write( "25  35   47\r<BR>\n" );
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document.write( "17   5   61\r<BR>\n" );
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document.write( "11   72  ? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #846423 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52781)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=846423\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .\r<BR>\n" );
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document.write( "If you have nothing to do, you may place \"x\" instead of the question mark,<BR>\n" );
document.write( "equate the determinant of the matrix to zero and solve for x.\r<BR>\n" );
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document.write( "Or, alternatively, you may require the sum of elements of the matrix to be equal to zero. <BR>\n" );
document.write( "Then you obtain another equation to determine the value of x.\r<BR>\n" );
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document.write( "Again, if you have nothing to do, you may entertain yourself doing it.\r<BR>\n" );
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document.write( "Third possible entertainment is to equate the trace of the matrix to zero (the sum of the diagonal elements)<BR>\n" );
document.write( "and find x from this equation.\r<BR>\n" );
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document.write( "Fourth possibility is to place any number instead of x, for example,\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;73, &nbsp;-289, &nbsp;<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%283%29 ALIGN=MIDDLE  ALT=\"sqrt%283%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, &nbsp;e, &nbsp;<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi ALIGN=MIDDLE  ALT=\"pi\"   DISABLED_style= \"max-width:90%; height:auto;\" >,  &nbsp;<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=e%5Epi ALIGN=MIDDLE  ALT=\"e%5Epi\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;or  &nbsp;<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi%5Ee ALIGN=MIDDLE  ALT=\"pi%5Ee\"   DISABLED_style= \"max-width:90%; height:auto;\" >,\r<BR>\n" );
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document.write( "since nothing in the problem prohibits you to do it.\r<BR>\n" );
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document.write( "Thus, if you really have nothing to do and struggle of it, you may have several ways to entertain yourself.\r<BR>\n" );
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document.write( "The only thing which I do not understand, is THIS: do you really think that at this forum I will entertain you ?\r<BR>\n" );
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document.write( "If you think so, you make very crude mistake: this forum is not for puzzles.\r<BR>\n" );
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document.write( "At this forum the tutors perform another job: we work to teach real students to real Math.\r<BR>\n" );
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document.write( "To come here for puzzles is the same as to come to a grocery store for hardware.\r<BR>\n" );
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document.write( "If you are seeking help for puzzles and want others entertain you and generally make <BR>\n" );
document.write( "your job substituting yourself, find another web-site/forum in the Internet.\r<BR>\n" );
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document.write( "If you stop posting your puzzles to this forum, we, the tutors, will be infinitely happy.\r<BR>\n" );
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document.write( "Have a super-nice day.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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