document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1210355>Question 1210355</A>: <I><SPAN STYLE=\"word-break: break-all;\"> what does the 'a' in the quadratic equation y=ax^2+bx+c represent?<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 #852015 by </B><A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><B>math_tutor2020(3817)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><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=852015\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "The 'a' is the leading coefficient. <BR>\n" );
document.write( "a, b, and c are placeholders for values. \r<BR>\n" );
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document.write( "If a > 0 then the parabola opens upward. <BR>\n" );
document.write( "For example consider y = 3x^2+5x-2 where a = 3<BR>\n" );
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document.write( "In contrast, now consider y = -4x^2-7x+1 where a = -4 this time.<BR>\n" );
document.write( "The parabola opens downward because a < 0.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28400%2C400%2C-5%2C5%2C-5%2C5%2C-100%2C-4x%5E2-7x%2B1%29 ALIGN=MIDDLE  ALT=\"graph%28400%2C400%2C-5%2C5%2C-5%2C5%2C-100%2C-4x%5E2-7x%2B1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "I recommend using either Desmos or GeoGebra as a graphing tool. <BR>\n" );
document.write( "There are many other similar tools as well.\r<BR>\n" );
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document.write( "Here is an interactive Desmos graph where you can adjust the value of 'a' to any number you want. <BR>\n" );
document.write( "Move the slider around to see how the graph changes.<BR>\n" );
document.write( "<a  rel=nofollow HREF=\"https://www.desmos.com/calculator/e0boawqc3q\">https://www.desmos.com/calculator/e0boawqc3q</a><BR>\n" );
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