document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=73724>Question 73724</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0028253264/algebrahomeworkh>glencoe algerbra 1</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> I dont understand rational expression with extraneous values.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #52825 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=52825\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I dont understand rational expression with extraneous values. <BR>\n" );
document.write( "----------<BR>\n" );
document.write( "Let's say you have rational expression (x^2+6x+5)/(x+1) = 0\r<BR>\n" );
document.write( "\n" );
document.write( "This fraction is zero only when the numerator is zero.<BR>\n" );
document.write( "So you set the numerator equal to zero and proceed to solve for \"x\".<BR>\n" );
document.write( "x^2+6x+5 = 0<BR>\n" );
document.write( "You factor to get:<BR>\n" );
document.write( "(x+1)(x+5)=0<BR>\n" );
document.write( "Then x=-1 or x=-5<BR>\n" );
document.write( "You think you have two solutions but you check them and find:<BR>\n" );
document.write( "If x=-1 you get [(-1)^2+6*(-1)+5] / (-1+1)= 0/0 which is undefined.<BR>\n" );
document.write( "so x=-1, which you thought was a solution, is not a solution .  It is extraneous.<BR>\n" );
document.write( "========<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );