document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=752631>Question 752631</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the equation log3(x)-log3(x-5)=1\r<BR>\n" );
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document.write( "I tried like this:\r<BR>\n" );
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document.write( "log3(x/x-5)=1<BR>\n" );
document.write( "3=(x/x-5)<BR>\n" );
document.write( "3*(x-5)=x<BR>\n" );
document.write( "3x-15=x<BR>\n" );
document.write( "2x=15<BR>\n" );
document.write( "x=15/2\r<BR>\n" );
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document.write( "but the answer should be x=5/4, where did I go wrong? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #457914 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=457914\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> you did nothing wrong.<BR>\n" );
document.write( "the correct answer is x = 15/2.\r<BR>\n" );
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document.write( "you can use your calculator to confirm.\r<BR>\n" );
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document.write( "log3(x) = log10(x) / log10(3)\r<BR>\n" );
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document.write( "since log10 is the calculator LOG function, this can be reduced to:\r<BR>\n" );
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document.write( "log3(x) = LOG(x) / LOG(3)\r<BR>\n" );
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document.write( "your answer is x = 15/2 = 7.5\r<BR>\n" );
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document.write( "replace x in the original equation with 7.5 and you will get:\r<BR>\n" );
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document.write( "log3(7.5) - log3(7.5-2) = 1<BR>\n" );
document.write( "this simplifies to:<BR>\n" );
document.write( "log3(7.5) - log3(2.5) = 1\r<BR>\n" );
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document.write( "use the conversion factor to make this equation:\r<BR>\n" );
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document.write( "log(7.5)/LOG(3) = LOG(2.5)/LOG(3) = 1\r<BR>\n" );
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document.write( "use your calculator to get:\r<BR>\n" );
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document.write( "1.8340437671 - .8340437671 = 1\r<BR>\n" );
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document.write( "this simplifies to 1 = 1.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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