document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=111223>Question 111223</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am graphing a parabola and I have all of my points done but I'm having a problem getting the x & y vertex's....the equation is 3x²-x-1=0 ...I have 1.5 for x but I'm told this is wrong and I have no idea how to solve it for the y vertex. Please help!<BR>\n" );
document.write( "            Thanks so much!<BR>\n" );
document.write( "                          B. Cook </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #81120 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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/cgi-bin/show-face.mpl?user=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=81120\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In general, for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ax%5E2%2Bbx%2Bc ALIGN=MIDDLE  ALT=\"ax%5E2%2Bbx%2Bc\"   DISABLED_style= \"max-width:90%; height:auto;\" >, vertex at (h, k), <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=-b%2F%282a%29 ALIGN=MIDDLE  ALT=\"h=-b%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=ah%5E2%2Bbh%2Bc ALIGN=MIDDLE  ALT=\"k=ah%5E2%2Bbh%2Bc\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
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document.write( "So, for your particular problem, b = -1 and a = 3.  That makes <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=%28-%28-1%29%29%2F%282%2A3%29=1%2F6 ALIGN=MIDDLE  ALT=\"h=%28-%28-1%29%29%2F%282%2A3%29=1%2F6\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=3%281%2F6%29%5E2-%281%2F6%29-1 ALIGN=MIDDLE  ALT=\"k=3%281%2F6%29%5E2-%281%2F6%29-1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=3%2F36-1%2F6-1 ALIGN=MIDDLE  ALT=\"k=3%2F36-1%2F6-1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=3%2F36-6%2F36-36%2F36 ALIGN=MIDDLE  ALT=\"k=3%2F36-6%2F36-36%2F36\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=-39%2F36 ALIGN=MIDDLE  ALT=\"k=-39%2F36\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Putting the vertex squarely on the point (1/6,-39/36)<BR>\n" );
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document.write( "Send me a note if there is any part of that you don't understand.<BR>\n" );
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document.write( "John </SPAN>\n" );
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