document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=552550>Question 552550</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I'm getting stuck on reciprocal.  I know that the opposite of -x is x but I can't remember or find the WHY we have to do that,  Here is the simple problem I can't seem to figure out because I want to learn why I have to do the opposite.\r<BR>\n" );
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document.write( "21 - x = 28<BR>\n" );
document.write( "Here's what I did:<BR>\n" );
document.write( "21 + (-x) = 28<BR>\n" );
document.write( "21-21+(-x) = 28-21<BR>\n" );
document.write( "-x = 7\r<BR>\n" );
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document.write( "I think I'm supposed to read this as \"the opposite of\" -x is X but how do I get the correct answer of -7?\r<BR>\n" );
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document.write( "Thanks for your help,\r<BR>\n" );
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document.write( "Ramar\r<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 #360382 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=360382\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 21 - x = 28<BR>\n" );
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document.write( "Add x<BR>\n" );
document.write( "21 = x + 28<BR>\n" );
document.write( "Subtract 28<BR>\n" );
document.write( "-7 = x<BR>\n" );
document.write( "x = -7<BR>\n" );
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