document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=552790>Question 552790</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the focus of a parabola is (4, -3) and the directrix is y=6\r<BR>\n" );
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document.write( "write the equation of the parabola and then draw the graph. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #360578 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=360578\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the focus of a parabola is (4, -3) and the directrix is y=6 <BR>\n" );
document.write( "write the equation of the parabola and then draw the graph<BR>\n" );
document.write( "**<BR>\n" );
document.write( "Equation is that of a parabola which opens downward. Its standard form: (x-h)^2=-4p(y-k), with (h,k) being the (x,y) coordinates of the vertex.<BR>\n" );
document.write( "For given equation:<BR>\n" );
document.write( "axis of symmetry: x=4<BR>\n" );
document.write( "p=half the distance between the directrix and y-coordinate of the focus on the axis of symmetry.<BR>\n" );
document.write( "p=(6+3)/2=9/2=4.5<BR>\n" );
document.write( "vertex: (4, 3/2)<BR>\n" );
document.write( "Equation of parabola:<BR>\n" );
document.write( "y=(x-4)^2/-18+3/2<BR>\n" );
document.write( "see graph below<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C%28x-4%29%5E2%2F-18%2B3%2F2%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C%28x-4%29%5E2%2F-18%2B3%2F2%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  </SPAN>\n" );
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