document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=148811>Question 148811</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I can't seem to get this one.\r<BR>\n" );
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document.write( "Find the vertex of the parabola.  y = -2x2 + 12x - 13 \r<BR>\n" );
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document.write( "Help!\r<BR>\n" );
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document.write( "Ellen </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #109149 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=109149\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the vertex of the parabola. y = -2x^2 + 12x - 13 <BR>\n" );
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document.write( "There are several ways to do this; one is to complete the square.<BR>\n" );
document.write( " -2x^2 + 12x - 13  = y<BR>\n" );
document.write( "  2x^2 - 12x  = -(y+13)<BR>\n" );
document.write( " Complete the square on the x-terms:<BR>\n" );
document.write( "2(x^2 - 6x + 9) = -y-13+18<BR>\n" );
document.write( "Factor:<BR>\n" );
document.write( "2(x-3)^2 = -(y-5)<BR>\n" );
document.write( "Vertex is at x=3, y=5<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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