document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=475472>Question 475472</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If your equation is -0.2x + x² + 0.2 = 0, does this parabola open up or down?  Which term's coefficient determines that?\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 #326043 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=326043\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Skip the \" = 0\" part, since the graph would be two points instead of a parabola.\r<BR>\n" );
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document.write( "The function f(x) = -0.2x + x^2 + 0.2 goes to positive infinity on both sides, so the parabola opens down. The x^2 coefficient determines this because it has the highest degree.\r<BR>\n" );
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document.write( " (I actually never learned a parabola \"opening up\" or \"opening down\" in school, it is a vague definition and hardly anyone uses that definition in higher-level mathematics.) </SPAN>\n" );
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