document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=668690>Question 668690</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 2+9=_ +2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #415767 by </B><A HREF=/tutors/aboutme.mpl?userid=swincher4391><B>swincher4391(1107)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=swincher4391><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=swincher4391><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=415767\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We know in general for x,y if we have x+y that's equal to y+x. This is what we call the commutative property of addition. So, where x =2 and y =9, we have:\r<BR>\n" );
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document.write( "x + y = y + x\r<BR>\n" );
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document.write( "2 + 9 = 9 + 2\r<BR>\n" );
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document.write( "So, the missing number is 9. </SPAN>\n" );
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