document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=197965>Question 197965</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find the focus and the directrix of the parabola.the vertex of the parabola is (0,0),i need help because i dont understand where to start persay \r<BR>\n" );
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document.write( "y= -1/20x^2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #148441 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=148441\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> find the focus and the directrix of the parabola.the vertex of the parabola is (0,0),i need help because i dont understand where to start persay <BR>\n" );
document.write( "y= -1/20x^2<BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "Put the equation into the form (x-h)^2 = 4p(y-k)<BR>\n" );
document.write( "(x-0)^2 = -20(y-0)<BR>\n" );
document.write( "-----------<BR>\n" );
document.write( "(h,k) = (0,0)<BR>\n" );
document.write( "4p = -20<BR>\n" );
document.write( "p = -5<BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "Vertex is at (h,k) = (0,0)<BR>\n" );
document.write( "Directrix is y = k-p = 0+5 = 5<BR>\n" );
document.write( "Focus is at (h,k+p) = (0,-5)<BR>\n" );
document.write( "-------------------------------------<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C%28-1%2F20%29x%5E2%29 ALIGN=MIDDLE  ALT=\"graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C%28-1%2F20%29x%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "=====================================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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