document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=28969>Question 28969</A>: <I><SPAN STYLE=\"word-break: break-all;\"> use completing the square to find the vertex of the quadratic function<BR>\n" );
document.write( "y=-2x^2+16x+4\r<BR>\n" );
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document.write( "This is what i tried<BR>\n" );
document.write( "y=-2(x^2-8x)+ 4<BR>\n" );
document.write( "Y= -2(x-4)^2 +16-16+4<BR>\n" );
document.write( "Y=-2(x-4)^2-12<BR>\n" );
document.write( "vertex= (-4,-12)   the answer is supposed to be vertex= (4,36)<BR>\n" );
document.write( "Thanks for the help in advance </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #15828 by </B><A HREF=/tutors/aboutme.mpl?userid=sdmmadam@yahoo.com><B>sdmmadam@yahoo.com(530)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sdmmadam@yahoo.com><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=15828\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> use completing the square to find the vertex of the quadratic function<BR>\n" );
document.write( "y=-2x^2+16x+4<BR>\n" );
document.write( "This is what i tried\r<BR>\n" );
document.write( "\n" );
document.write( "y=-2x^2+16x+4<BR>\n" );
document.write( "y =-2[x^2-8x-2]<BR>\n" );
document.write( "y = -2{[(x-4)^2-16] -2}<BR>\n" );
document.write( "(perfecting the square for which we needed 16 and hence added and subtracted 16)<BR>\n" );
document.write( "y = -2{(x-4)^2-18) <BR>\n" );
document.write( "y = -2(x-4)^2 +36<BR>\n" );
document.write( "(y-36) = -2(x-4)^2<BR>\n" );
document.write( "(-1/2)(y-36)= (x-4)^2   (multiplying by (-1/2) )<BR>\n" );
document.write( "That is  (x-4)^2= -4(1/8)(y-36)<BR>\n" );
document.write( "which is of the form (x-h)^2 = -4a(y-k)<BR>\n" );
document.write( "Square in x and linear in y represents a parabola with axis vertical <BR>\n" );
document.write( "and since the coefficient of y is negative,the parabola looks downwards (that is the union symbol inverted)<BR>\n" );
document.write( "Vertex = A(h,k) = (4,36)<BR>\n" );
document.write( "a = distance of the focus from the vertex <BR>\n" );
document.write( "=(1/8)<BR>\n" );
document.write( "That is the focus is  the point S(4,36-1/8) = S(4,287/8) which is a point <BR>\n" );
document.write( "on the line of symmetry, x=4 <BR>\n" );
document.write( "and (1/8) unit below the vetex<BR>\n" );
document.write( " </SPAN>\n" );
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