document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=81128>Question 81128</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do I find the vertex of the following parabola\r<BR>\n" );
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document.write( "f(x)= -x^2 + 9x -5 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #58165 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=58165\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the vertex is on the axis of symmetry; the general equation of which is x=-b/2a ... in this case, x=-9/(-2), or x=4.5\r<BR>\n" );
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document.write( "so the x value for the vertex is 4.5 ... to find the y value, just 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=y=-%284.5%5E2%29%2B9%284.5%29-5 ALIGN=MIDDLE  ALT=\"y=-%284.5%5E2%29%2B9%284.5%29-5\"   DISABLED_style= \"max-width:90%; height:auto;\" > ... so y=15.25 ... vertex is (4.5,15.25) </SPAN>\n" );
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