document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=189148>Question 189148</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I should solve this equation\r<BR>\n" );
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document.write( "9/(x+1) - 2/(x-2) = 5/(x+1)\r<BR>\n" );
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document.write( "I can solve it but it says check all proposed solutions! What does it mean? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #141892 by </B><A HREF=/tutors/aboutme.mpl?userid=vleith><B>vleith(2983)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vleith><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=141892\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Once you solve for all x that 'work', you need to check those values to ensure they do not end up being an invalid answer.\r<BR>\n" );
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document.write( "For instance, if x = -1 or x=2 end up being solutions for this problem, then you can't use them. Both of those values result in a denominator that is 0. \r<BR>\n" );
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document.write( "This applies to every problem. When you solve for roots, all you get are 'possible' answers. You always need to take a look at those possible answers to verify that they are, in fact, valid.\r<BR>\n" );
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document.write( "Another common place where a possible answer is invalid are problems that ask for the 'length' of something. Many times, the possible solutions will include at least one negative value. Since a 'length' can't be negative, those answers are invalid too. \r<BR>\n" );
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document.write( "Hope that helps<BR>\n" );
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