document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1039377>Question 1039377</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Identify the equation of the parabola with its focus at (-4,9) and the directrix y=-3. <BR>\n" );
document.write( "A) 24(y-7)=(x+4)^2 <BR>\n" );
document.write( "B) -12(y+4)=(x+4)^2 <BR>\n" );
document.write( "C) 24(y-3)=(x+4)^2 <BR>\n" );
document.write( "D) 12(y-4)=(x+4)^2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #654126 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=654126\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You can use those pieces of information and the distance formula to derive the equation.   A set of points (x,y)  is the same distance from  (-4,9) as from (x,-3).  Put into the formula,\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28%28x-%28-4%29%29%5E2%2B%28y-9%29%5E2%29=sqrt%28%28x-x%29%5E2%2B%28y-%28-3%29%29%5E2%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "Simplify this.\r<BR>\n" );
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document.write( "First step after that initial equation could be<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x%2B4%29%5E2%2B%28y-9%29%5E2=%28y%2B3%29%5E2 ALIGN=MIDDLE  ALT=\"%28x%2B4%29%5E2%2B%28y-9%29%5E2=%28y%2B3%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and keep going to whatever form of the equation you need for making a comparison to your choices.\r<BR>\n" );
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document.write( "Study this demonstration:<BR>\n" );
document.write( "<a  rel=nofollow HREF=\"https://www.youtube.com/watch?v=Wworlx39KfQ\">Equation of parabola given focus and directrix - Vertex not at the origin - video</a> </SPAN>\n" );
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