document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=408961>Question 408961</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This one is really stumping me... Havent got into the ln function yet, only using log base 10 at this point\r<BR>\n" );
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document.write( "Solve the following exponential equation using logarithms:<BR>\n" );
document.write( "(3^2x)-(3^x)=216 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #288007 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=288007\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (3^2x)-(3^x)=216<BR>\n" );
document.write( "Sub w for 3^x<BR>\n" );
document.write( "--> w^2 - w - 216 = 0<BR>\n" );
document.write( "w = 1/2 + sqrt(865)/2 (the 2nd solution is negative, and can't be used)<BR>\n" );
document.write( "Sub back<BR>\n" );
document.write( "3^x = 1/2 ± sqrt(865)/2<BR>\n" );
document.write( "3^x =~ 15.20544<BR>\n" );
document.write( "x*log(3) = log(15.20544)<BR>\n" );
document.write( "x = log(15.20544)/log(3)<BR>\n" );
document.write( "x =~ 2.477<BR>\n" );
document.write( "------------------- </SPAN>\n" );
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