document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1109900>Question 1109900</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Twice the difference of a number and 9 is 7. \r<BR>\n" );
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document.write( "Translate the sentence into an equation. <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 #724867 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13203)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=724867\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "You have to be a bit careful with this....<br><BR>\n" );
document.write( "In everyday usage, the difference between two numbers is always thought of as being a positive number.  So the difference of 8 and 3 is 5, and the difference of 3 and 8 is 5.<br><BR>\n" );
document.write( "That is (I assume) why the other tutor used absolute value symbols in her equation.<br><BR>\n" );
document.write( "But often in mathematics, the context tells you that \"the difference of a and b\" means ONLY a-b, and not the other way around.  So the difference of 8 and 3 would still be 5 (8-3=5); but the difference of 3 and 8 would be -5 (3-8 = -5).<br><BR>\n" );
document.write( "In your question, there is no context to help us decide whether or not the answer has to be positive.  Therefore, I would suggest a better translation of the given statement is<br><BR>\n" );
document.write( "2(x-9) = 7<br><BR>\n" );
document.write( "rather than<br><BR>\n" );
document.write( "2|x-9| = 7 </SPAN>\n" );
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