document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=319410>Question 319410</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the vertex of f(x)=-x^2+2x+4?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #228735 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=228735\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> f(x)=-x^2+2x+4<BR>\n" );
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document.write( "The x-coordinate is the \"axis of symmetry\":<BR>\n" );
document.write( "x = -b/(2a) = -2/(-2) = 1<BR>\n" );
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document.write( "To find the y-coordinate, plug it in:<BR>\n" );
document.write( "f(1) = -1^2+2(1)+4<BR>\n" );
document.write( "f(1) = -1+2+4<BR>\n" );
document.write( "f(1) = 5<BR>\n" );
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document.write( "vertex the is at (1,5)<BR>\n" );
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