document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1181713>Question 1181713</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Toby is n years old and Adrian is d years younger than Toby.<BR>\n" );
document.write( "Write down a formula for S where S years is the sum of their ages.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #811614 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=811614\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> n = toby's age.<BR>\n" );
document.write( "n - d = adrian's age.<BR>\n" );
document.write( "the sum of their ages is equal to n + n - d = 2n - d<BR>\n" );
document.write( "when the sum of their ages is equal to S, that formula is S = 2n - d<BR>\n" );
document.write( "when S = 5, that formula becomes 5 = 2n - d<BR>\n" );
document.write( "that should be your answer.\r<BR>\n" );
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document.write( "please keep in mind that, if the sum of their ages is 5, then there is a limit for the value of n.\r<BR>\n" );
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document.write( "that limit is that n can only be between 2.5 and 5.\r<BR>\n" );
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document.write( "when n = 2.5, then 5 = 2n - d becomes 5 = 5 - d which makes d = 0<BR>\n" );
document.write( "when n = 5, then 5 = 2n - d becomes 5 = 10 - d which makes d = 5.\r<BR>\n" );
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document.write( "if n is less than 2.5, say 2, then S = 2n - d becomes S = 4 - d which makes d = negative which means that adrian is older than toby which can't be.\r<BR>\n" );
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document.write( "if n is greater than 5, then the sum of their ages can only be 5 if adrian's age is less than 0 which can't be.\r<BR>\n" );
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document.write( "the formula is good, but only if n is between 2.5 and 5.\r<BR>\n" );
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document.write( "just keep in mind that there are limits to the value of n for the answer to be valid because toby's age and adrian's age must both be greater than or equal to 0.\r<BR>\n" );
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document.write( "those limits are that n can only be between 2.5 and 5.\r<BR>\n" );
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document.write( "since they only asked you for the formula, then your answer is that the formula is 5 = 2n - d\r<BR>\n" );
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document.write( " </SPAN>\n" );
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