document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=832240>Question 832240</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do you find the P and the directrix of the equation of a parabola with its focus on (4,-2) and a vertex of (4,-4)? \r<BR>\n" );
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document.write( "I tried solving for P but I don't know if it's correct. Here's my solution for P:\r<BR>\n" );
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document.write( "Since focus is (h + P, k) in terms of y or (h, P + k)in terms of x, I don't know if the equation is in terms of y or x, so I just made a guess, so: (4 + P, -4);  P=-4 or (4, P - 4); P=4? \r<BR>\n" );
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document.write( "And also, how do you find P if vertex is at (2,1) and the directrix is at x = -2?\r<BR>\n" );
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document.write( "I'm really confused in finding for P but I understand how the basics work in conic sections. Your help will be really appreciated.\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 #502153 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=502153\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How do you find the P and the directrix of the equation of a parabola with its focus on (4,-2) and a vertex of (4,-4)?<BR>\n" );
document.write( "how do you find P if vertex is at (2,1) and the directrix is at x = -2? <BR>\n" );
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document.write( "In the first case, parabola opens upward.<BR>\n" );
document.write( "Its basic equation: (x+h)^2=4p(y-k)<BR>\n" );
document.write( "(x-4)^2=4p(y+4)<BR>\n" );
document.write( "axis of symmetry: x=4<BR>\n" );
document.write( "focus: (4,-2)<BR>\n" );
document.write( "p=2 (distance(-2 to -4) from focus to vertex on the axis of symmetry)<BR>\n" );
document.write( "directrix: y=-6<BR>\n" );
document.write( "..<BR>\n" );
document.write( "In the 2nd case, parabola opens rightward. <BR>\n" );
document.write( "axis of symmetry: y=1<BR>\n" );
document.write( "p=4 (distance(-2 to 2) from directrix to vertex on the axis of symmetry)<BR>\n" );
document.write( "focus: (6,1) </SPAN>\n" );
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