document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=983230>Question 983230</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the vertex, focus, directrix, and focal width of the parabola.\r<BR>\n" );
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document.write( "-1/40 x^2= y </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #604038 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=604038\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> -1/40 x^2= y\r<BR>\n" );
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document.write( "-(1/40)x^2=y\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-%281%2F40%29x%5E2=y ALIGN=MIDDLE  ALT=\"-%281%2F40%29x%5E2=y\"   DISABLED_style= \"max-width:90%; height:auto;\" >  or as <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2=-40y ALIGN=MIDDLE  ALT=\"x%5E2=-40y\"   DISABLED_style= \"max-width:90%; height:auto;\" > or still equivalently  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28-40y=x%5E2%29 ALIGN=MIDDLE  ALT=\"highlight_green%28-40y=x%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Compare that green outlined equation to the basic form,  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4p=x%5E2 ALIGN=MIDDLE  ALT=\"4p=x%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "A video which explains this well  (but a little bit clumsy) is this one:<BR>\n" );
document.write( "<a  rel=nofollow HREF=\"https://www.youtube.com/watch?v=M8LGsQMwwj4\">Equation Derivation for Parabola from Focus and Directrix</a> </SPAN>\n" );
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