document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=95122>Question 95122</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am confused about this question.  I have a graph with points (-1,0), (0.67,0) and (-0.16,-2) which is the vertex.  I'm supposed to comment on the discriminant and form a quadratic equation and solve it.  I came up with several equations which are not correct.  Can someone help me?  Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #69287 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=69287\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I am confused about this question.  I have a graph with points (-1,0), (0.67,0) and (-0.165,-2) which is the vertex.  I'm supposed to comment on the discriminant and form a quadratic equation and solve it.  I came up with several equations which are not correct.<BR>\n" );
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document.write( "Plot those points and you will see the vertex is below the x-axis and the<BR>\n" );
document.write( "parabola has two Real Number zeroes: x=-1 and x=0.67<BR>\n" );
document.write( "So the discriminant, b^2-4ac, must be greater than zero.<BR>\n" );
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document.write( "With zeros at x=-1 and x = 0.67<BR>\n" );
document.write( "f(x) = a(x+1)(x-0.67)<BR>\n" );
document.write( "But the vertex says f(-0.165)=-2<BR>\n" );
document.write( "So -2 = a(-0.165+1)(-0.165-0.67)<BR>\n" );
document.write( "-2 = a*0.835*-0.835<BR>\n" );
document.write( "a = 0.8685<BR>\n" );
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document.write( "EQUATIOn:<BR>\n" );
document.write( "f(x)= 2.8685..(x+1)(x-0.67)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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