document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=4506>Question 4506</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Change to exponential form\r<BR>\n" );
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document.write( "log  10^x + log 10 (x + 15) = 2\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log+%2810%2C+x%29+%2B+log+%2810%2C+%28x%2B15%29%29+=+2 ALIGN=MIDDLE  ALT=\"log+%2810%2C+x%29+%2B+log+%2810%2C+%28x%2B15%29%29+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #2049 by </B><A HREF=/tutors/aboutme.mpl?userid=rapaljer><B>rapaljer(4671)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rapaljer><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=rapaljer><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=2049\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log+%2810%2C+x%29+%2B+log+%2810%2C+%28x%2B15%29%29+=+2 ALIGN=MIDDLE  ALT=\"log+%2810%2C+x%29+%2B+log+%2810%2C+%28x%2B15%29%29+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "By the first law of logarithms, log M + log N = log MN<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=log+%2810%2C+x%28x%2B15%29%29+=+2 ALIGN=MIDDLE  ALT=\"log+%2810%2C+x%28x%2B15%29%29+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Convert from logarithmic notation to exponential form by writing this as<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10%5E2+=+x%28x%2B15%29 ALIGN=MIDDLE  ALT=\"10%5E2+=+x%28x%2B15%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=100+=+x%5E2+%2B+15x ALIGN=MIDDLE  ALT=\"100+=+x%5E2+%2B+15x\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Set equal to zero:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+x%5E2+%2B+15x+-+100 ALIGN=MIDDLE  ALT=\"0+=+x%5E2+%2B+15x+-+100\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Factor the trinomial:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+=+%28x+%2B+20%29%28x+-+5%29 ALIGN=MIDDLE  ALT=\"0+=+%28x+%2B+20%29%28x+-+5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Therefore x = -20 or x = 5.  \r<BR>\n" );
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document.write( "However, if x = -20, then the original equation results in log (-20) + log (-5) which is not a real number, so this answer must be rejected.\r<BR>\n" );
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document.write( "Final answer is x = 5 the only possible solution.\r<BR>\n" );
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document.write( "R^2 at SCC </SPAN>\n" );
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