document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=184785>Question 184785</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi,\r<BR>\n" );
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document.write( "The problem is a common one: The ages of a certain father and son are the same with the digits reversed. Nine years ago, the father was twice as old as the son. How old are they now?\r<BR>\n" );
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document.write( "I know what the answer is - that is trivial. I am after an ALGEBRAIC solution, if their is one.\r<BR>\n" );
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document.write( "Thank You,<BR>\n" );
document.write( "Michael L. Giancola<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 #138678 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=138678\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The ages of a certain father and son are the same with the digits reversed.<BR>\n" );
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document.write( "here is some algebra with a little \"try & see\"<BR>\n" );
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document.write( "Let 10x + y = Father's age<BR>\n" );
document.write( "then<BR>\n" );
document.write( "10y + x = son's age<BR>\n" );
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document.write( "\"Nine years ago, the father was twice as old as the son.\"<BR>\n" );
document.write( "(10x+y) - 9 = 2((10y+x)-9)<BR>\n" );
document.write( "10x + y - 9 = 20y + 2x - 18<BR>\n" );
document.write( "10x - 2x = 20y - y - 18 + 9<BR>\n" );
document.write( "8x = 19y - 9<BR>\n" );
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document.write( " How old are they now? <BR>\n" );
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document.write( "We know that x and y are single digit integers<BR>\n" );
document.write( "y = 3 is the only one that will satisfy<BR>\n" );
document.write( "8x = 19(3) - 9<BR>\n" );
document.write( "8x = 57 - 9<BR>\n" );
document.write( "8x = 48<BR>\n" );
document.write( "x = 6<BR>\n" );
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document.write( "Dad is 63, son is 36<BR>\n" );
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document.write( "Check in the statement:<BR>\n" );
document.write( "\" Nine years ago, the father was twice as old as the son.\"<BR>\n" );
document.write( "63 - 9 = 2(36 - 9)<BR>\n" );
document.write( "54 = 2(27)  </SPAN>\n" );
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