document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=177689>Question 177689</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find all numbers for which the rational expression is undefined.<BR>\n" );
document.write( "r^3-8r<BR>\n" );
document.write( "r^2-16<BR>\n" );
document.write( "(Use comma to separate answers.)<BR>\n" );
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document.write( "I am not sure what I am doing here<BR>\n" );
document.write( "thank you in advance for your help </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #132692 by </B><A HREF=/tutors/aboutme.mpl?userid=user_dude2008><B>user_dude2008(1862)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=user_dude2008><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=132692\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Undefined when denominator is 0\r<BR>\n" );
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document.write( "r^2-16 = 0\r<BR>\n" );
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document.write( "(r+4)(r-4) = 0\r<BR>\n" );
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document.write( "r+4=0 , r-4=0\r<BR>\n" );
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document.write( "r=-4, r=4\r<BR>\n" );
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document.write( "Answer: -4, 4<BR>\n" );
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