document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1077364>Question 1077364</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The sum of the digits of a two-digits number 7. Tve ten's digit is one more than twice the  units digit. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #691832 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=691832\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let:<BR>\n" );
document.write( "a=ten's digit<BR>\n" );
document.write( "b=one's digit\r<BR>\n" );
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document.write( "a+b = 7   (1)<BR>\n" );
document.write( "a = 2b+1   (2)\r<BR>\n" );
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document.write( "Substitute for 'a' from (2), into (1):   (2b+1)+b = 7<BR>\n" );
document.write( "                                       3b+1 = 7<BR>\n" );
document.write( "                                        3b = 6<BR>\n" );
document.write( "                                          b = 2   —>  a = 2(2) + 1 = 5\r<BR>\n" );
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document.write( "—<BR>\n" );
document.write( "Ans: The number is 52<BR>\n" );
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document.write( " </SPAN>\n" );
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