document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=458635>Question 458635</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Write an equation for the parabola with focus (4,0) and directrix y=2.\r<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 #314715 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=314715\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Write an equation for the parabola with focus (4,0) and directrix y=2. <BR>\n" );
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document.write( "Standard form of parabola: (x-h)^2=4p(y-k), with (h,k) being the (x,y) coordinates of the vertex<BR>\n" );
document.write( "Given parabola opens downward with axis of symmetry at x=4. Vertex at (4,1). p=1<BR>\n" );
document.write( "Equation of parabola:<BR>\n" );
document.write( "(x-4)^2=-4(y-1) (ans)<BR>\n" );
document.write( "see the graph below as a visual check on the answer<BR>\n" );
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document.write( "y=1-(x-4)^2/4\r<BR>\n" );
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