document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=267268>Question 267268</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need to represent the following as an equation:  \"The sum of a certain two-digit number is 7.  Reversing its digits increases the number by 9.  What is the number?\"  The answer is 34.  But, how do you represent the first 1/2 of the problem in an equation?  I came up with several ways to represent the part of the equation that is the second half of the problem.  I do not know how to represent \"the sum of a certain two-digit number\"... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #196189 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=196189\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let t = tens digit and u = units digit\r<BR>\n" );
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document.write( "Any two digit number is of the form <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10t%2Bu ALIGN=MIDDLE  ALT=\"10t%2Bu\"   DISABLED_style= \"max-width:90%; height:auto;\" > where 't' and 'u' are whole numbers. For example, the number 23 has a tens digit of 2 and a units digit of 3. So t=2 and u=3 which means that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10t%2Bu=10%282%29%2B3=20%2B3=23 ALIGN=MIDDLE  ALT=\"10t%2Bu=10%282%29%2B3=20%2B3=23\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Because \"The sum of the digits of a certain two-digit number is 7\", we know that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%2Bu=7 ALIGN=MIDDLE  ALT=\"t%2Bu=7\"   DISABLED_style= \"max-width:90%; height:auto;\" >. So this the first equation.\r<BR>\n" );
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document.write( "And since \"Reversing its digits increases the number by 9\", this tells us that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10u%2Bt=10t%2Bu%2B9 ALIGN=MIDDLE  ALT=\"10u%2Bt=10t%2Bu%2B9\"   DISABLED_style= \"max-width:90%; height:auto;\" >. This is the second equation.\r<BR>\n" );
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document.write( "I'll let you solve the system of equations. </SPAN>\n" );
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