document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=643069>Question 643069</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can someone please help me with this problem?<BR>\n" );
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document.write( "Determine the value of the unknown.<BR>\n" );
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document.write( "log81^(A-4) = -(1/4)<BR>\n" );
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document.write( "A = __?__\r<BR>\n" );
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document.write( "Thank you! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #404324 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=404324\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> log81^(A-4) = -(1/4)<BR>\n" );
document.write( "(A-4)log81=-.25<BR>\n" );
document.write( "Alog81-4log81=-.25<BR>\n" );
document.write( "Alog81=4log81-.25<BR>\n" );
document.write( "A=(4log81-.25)/log81<BR>\n" );
document.write( "using calculator<BR>\n" );
document.write( "A=3.869..\r<BR>\n" );
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document.write( "check:<BR>\n" );
document.write( "log81^(A-4)<BR>\n" );
document.write( "=log[81^(3.869-4)]<BR>\n" );
document.write( "=log[81^(-.131)]&#8776;-.2500..<BR>\n" );
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