document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=85942>Question 85942</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/061838670X/algebrahomeworkh>College Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Find the vertex, focus, and directrix of the parabola given by each equation.  Sketch the graph.\r<BR>\n" );
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document.write( "18.  3x+y^2+8y+4=0 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #62189 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=62189\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the vertex, focus, and directrix of the parabola given by each equation.  Sketch the graph.\r<BR>\n" );
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document.write( "18.  3x+y^2+8y+4=0<BR>\n" );
document.write( "Form: (y-k)^2=4p(x-h)<BR>\n" );
document.write( "y^2+8y+(8/2)^2 = -3x-4+(8/2)^2<BR>\n" );
document.write( "(y+4)^2 = -3x+12<BR>\n" );
document.write( "(y+4)^2 = -3(x-4)<BR>\n" );
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document.write( "4p=-3<BR>\n" );
document.write( "p=-3/4<BR>\n" );
document.write( "---------<BR>\n" );
document.write( "Vertex at  (h,k); (4,-4)<BR>\n" );
document.write( "focus at  (h+p,k); (4-3/4,-4) = (11/4,-4)<BR>\n" );
document.write( "directrix:at x=h-p; x= 4-(-3/4)) = 19/4<BR>\n" );
document.write( "=========<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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