document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1010890>Question 1010890</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I don't understand how to complete this problem: Write an equation for the parabola whose vertex is at (2,6) and which passes through (4,-1). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #626401 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=626401\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The vertex form is y=a(x-h)^2+k, where the vertex is (h,k)\r<BR>\n" );
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document.write( "That means y=a(x-2)^2+6<BR>\n" );
document.write( "Now, use the point given to solve for a.<BR>\n" );
document.write( "-1=a(2)^2+6, (x-2)^2=2^2, if x=4<BR>\n" );
document.write( "-1=4a+6<BR>\n" );
document.write( "4a=-7<BR>\n" );
document.write( "a=(-7/4)<BR>\n" );
document.write( "(-7/4){x^2-4x+4)+6=<BR>\n" );
document.write( "-(7/4)x^2+7x-7+6=-(7/4)x^2+7x-1<BR>\n" );
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