document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=822396>Question 822396</A>: <I><SPAN STYLE=\"word-break: break-all;\"> log base 10 (x+4) + log base 10 (x+1) = 1 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #498835 by </B><A HREF=/tutors/aboutme.mpl?userid=LinnW><B>LinnW(1048)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=LinnW><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=LinnW><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=498835\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> log base 10 (x+4) + log base 10 (x+1) = 1<BR>\n" );
document.write( "log(x+4) + log(x+1) = 1<BR>\n" );
document.write( "Since log(10) = 1<BR>\n" );
document.write( "log(x+4) + log(x+1) = log(10)<BR>\n" );
document.write( "log((x+4)*(x+1)) = log(10)<BR>\n" );
document.write( "(x+4)*(x+1) = 10<BR>\n" );
document.write( "x^2 + 5x + 4 = 10<BR>\n" );
document.write( "subtract 10 from each side<BR>\n" );
document.write( "x^2 + 5x - 6 = 0<BR>\n" );
document.write( "(x+6)(x-1) = 0<BR>\n" );
document.write( "x = -6 or x = 1<BR>\n" );
document.write( "substituting in log(x+4) + log(x+1) = 1 and x = 1<BR>\n" );
document.write( "log(1+4) + log(1+1) ?= 1<BR>\n" );
document.write( "log(5) + log(2) ?= 1<BR>\n" );
document.write( "log(5*2) ?= 1<BR>\n" );
document.write( "log(10) ?= 1   Yes this looks good.<BR>\n" );
document.write( "So x = 1<BR>\n" );
document.write( "A negative value for x will not work. </SPAN>\n" );
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