document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=71846>Question 71846</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve for x in the following eguation.\r<BR>\n" );
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document.write( "5=9^x-1\r<BR>\n" );
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document.write( "(as in x-1 are exponents.) <BR>\n" );
document.write( "I can't figure out where the log goes... :( </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #51380 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=51380\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The log of base 9 goes on both sides. The log undoes an exponent, so we use the log on the entire right side, but we must do it to both sides.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5=9%5E%28x-1%29 ALIGN=MIDDLE  ALT=\"5=9%5E%28x-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log_%5B9%5D%285%29=log_%5B9%5D%289%5E%28x-1%29%29 ALIGN=MIDDLE  ALT=\"log_%5B9%5D%285%29=log_%5B9%5D%289%5E%28x-1%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >Take the log of both sides.The log simply cancels out the base 9<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log_%5B9%5D%285%29=+x-1 ALIGN=MIDDLE  ALT=\"log_%5B9%5D%285%29=+x-1\"   DISABLED_style= \"max-width:90%; height:auto;\" >Add 1 to both sides<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log_%5B9%5D%285%29%2B1=x ALIGN=MIDDLE  ALT=\"log_%5B9%5D%285%29%2B1=x\"   DISABLED_style= \"max-width:90%; height:auto;\" >Since log_[9](5) is a number we can find x<BR>\n" );
document.write( "Use the change of base formula<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log_%5Bb%5D%28x%29=log%28x%29%2Flog%28b%29 ALIGN=MIDDLE  ALT=\"log_%5Bb%5D%28x%29=log%28x%29%2Flog%28b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >Where b is the base and x is the argument. Remember the base of the log is assumed to be 10 if not specified.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=log%285%29%2Flog%289%29%2B1 ALIGN=MIDDLE  ALT=\"x=log%285%29%2Flog%289%29%2B1\"   DISABLED_style= \"max-width:90%; height:auto;\" >So this can be evaluated on a calculator<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=0.69897%2F0.95424+%2B+1 ALIGN=MIDDLE  ALT=\"x=0.69897%2F0.95424+%2B+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=0.73248+%2B+1 ALIGN=MIDDLE  ALT=\"x=0.73248+%2B+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1.73248 ALIGN=MIDDLE  ALT=\"x=1.73248\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Check:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5=9%5E%281.73248-1%29 ALIGN=MIDDLE  ALT=\"5=9%5E%281.73248-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5=9%5E%280.73248%29 ALIGN=MIDDLE  ALT=\"5=9%5E%280.73248%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5=4.99993 ALIGN=MIDDLE  ALT=\"5=4.99993\"   DISABLED_style= \"max-width:90%; height:auto;\" > Which is close enough to 5 (there are some roundoff errors). </SPAN>\n" );
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