document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=436468>Question 436468</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How is x-5 a factor of the polynomial x^2-x-20?  I know that x-5 is the answer but I have no idea how to do this.\r<BR>\n" );
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document.write( "Thanks for your help,<BR>\n" );
document.write( "Sarah </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #301975 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=301975\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve x - 5 = 0, or x = 5.  Then substitute into the equation:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%5E2+-+5+-+20+=+25+-+5+-+20+=+0 ALIGN=MIDDLE  ALT=\"5%5E2+-+5+-+20+=+25+-+5+-+20+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so 5 is a root.  Then by the factor theorem (if a is a root then x - a is a factor), x - 5 is a factor. </SPAN>\n" );
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