document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=427585>Question 427585</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the solution of the exponential equation 15^x = 4 in terms of logarithms, or correct to at least 4 decimal places. Please help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #297397 by </B><A HREF=/tutors/aboutme.mpl?userid=Gogonati><B>Gogonati(855)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Gogonati><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=Gogonati><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=297397\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solution:<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15%5Ex=4 ALIGN=MIDDLE  ALT=\"15%5Ex=4\"   DISABLED_style= \"max-width:90%; height:auto;\" > By definition of logarithms we write:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log%2815%2C4%29=x ALIGN=MIDDLE  ALT=\"log%2815%2C4%29=x\"   DISABLED_style= \"max-width:90%; height:auto;\" > or\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=%28ln4%29%2F%28ln15%29 ALIGN=MIDDLE  ALT=\"x=%28ln4%29%2F%28ln15%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "  x=0.5119 </SPAN>\n" );
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