document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=237615>Question 237615</A>: <I><SPAN STYLE=\"word-break: break-all;\"> z(z-9)=-20 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #174715 by </B><A HREF=/tutors/aboutme.mpl?userid=nyc_function><B>nyc_function(2741)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nyc_function><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=nyc_function><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=174715\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> z(z-9)=-20\r<BR>\n" );
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document.write( "z^2 - 9z = - 20\r<BR>\n" );
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document.write( "z^2 - 9z + 20 = 0\r<BR>\n" );
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document.write( "What two numbers when multiplied together will yield 20 but when added will yield -9?\r<BR>\n" );
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document.write( "How about -4 times -5?\r<BR>\n" );
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document.write( "(z - 4)(z - 5) = 0\r<BR>\n" );
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document.write( "Set each factor to zero and solve for z individually.\r<BR>\n" );
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document.write( "z - 4 = 0\r<BR>\n" );
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document.write( "z = 4\r<BR>\n" );
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document.write( "z - 5 = 0\r<BR>\n" );
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document.write( "z = 5\r<BR>\n" );
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document.write( "Solution: z = 4 and z = 5 </SPAN>\n" );
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