document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=114519>Question 114519</A>: <I><SPAN STYLE=\"word-break: break-all;\"> f(x)=-x^2+4x-9\r<BR>\n" );
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document.write( "Find the vertex<BR>\n" );
document.write( "What is the extremum value of the function? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #83470 by </B><A HREF=/tutors/aboutme.mpl?userid=HyperBrain><B>HyperBrain(694)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=HyperBrain><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=83470\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Please read my lesson---Shortcut in finding the vertex of any parabola\r<BR>\n" );
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document.write( "IF <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-x%5E2%2B4x-9 ALIGN=MIDDLE  ALT=\"y=-x%5E2%2B4x-9\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dy%2F%28dx%29=-2x%2B4 ALIGN=MIDDLE  ALT=\"dy%2F%28dx%29=-2x%2B4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Equating to zero,\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2x%2B4=0 ALIGN=MIDDLE  ALT=\"-2x%2B4=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2x=-4 ALIGN=MIDDLE  ALT=\"-2x=-4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1%2F2 ALIGN=MIDDLE  ALT=\"x=1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Solving for y,\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-%281%2F2%29%5E2%2B4%281%2F2%29-9=-31%2F4 ALIGN=MIDDLE  ALT=\"y=-%281%2F2%29%5E2%2B4%281%2F2%29-9=-31%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Thus, the vertex is at (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2%29 ALIGN=MIDDLE  ALT=\"1%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-31%2F4 ALIGN=MIDDLE  ALT=\"-31%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" >)\r<BR>\n" );
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document.write( "Power up,\<BR>\n" );
document.write( "HyperBrain! </SPAN>\n" );
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