document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=129643>Question 129643</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Okay, I'm trying to help my 13-year-old with Algebra.  Some of it I remember, but I can't recall what to do with fractional exponents.  The problem is:  <BR>\n" );
document.write( "(81)^-3/4.  I have tried everything that I can think of, but to no avail.  I don't know what to do with the negative sign when dealing with a negative fractional exponent.  I know what to do with it when it's just a negative exponent, but the negative fractional exponent is throwing me.  <BR>\n" );
document.write( "Thanks,<BR>\n" );
document.write( "Downs in Georgia </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #94651 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=94651\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x^-n=1/x^n\r<BR>\n" );
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document.write( "So, 81 raised to the -3/4 power equals 1/81 raised to the 3/4 power and this equals the (4th root of 1/81)^3\r<BR>\n" );
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document.write( "4th root of 1/81=1/3 because 1/3*1/3*1/3*1/3=1/81<BR>\n" );
document.write( "and (1/3)^3=1/27 because 1/3*1/3*1/3=1/27\r<BR>\n" );
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document.write( "Hope this helps--ptaylor </SPAN>\n" );
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