document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=38474>Question 38474</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Why must units of an expression be the same in order to be combined?   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #24069 by </B><A HREF=/tutors/aboutme.mpl?userid=lyra><B>lyra(94)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lyra><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=lyra><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=24069\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I am assuming that you mean 2x+3y that can't be added.  Well, think of it this way.  You have 2 oranges and 3 apples.  You cannot possibly give a total unless you say 5 fruits.  There is no fruit orange+apple.  Also <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y%2By%5E2 ALIGN=MIDDLE  ALT=\"y%2By%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > cannot be added because although they are both apples think of them as red and green apples.  There aren't red green apples.\r<BR>\n" );
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document.write( "Hope this helps and feel free to contact me with further questions,<BR>\n" );
document.write( "lyra </SPAN>\n" );
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