document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=4633>Question 4633</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How does one find the particular equation of the quadratic function that passes through a vertex of (5, -1) and the point (8, -28)? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #2153 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=2153\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> depends how much maths you know :-)\r<BR>\n" );
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document.write( "General quadratic is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=ax%5E2%2Bbx%2Bc ALIGN=MIDDLE  ALT=\"y=ax%5E2%2Bbx%2Bc\"   DISABLED_style= \"max-width:90%; height:auto;\" >. Put in both sets of (x,y) to get 2 equations in a and b. Solve these and ten re-write the general equation.\r<BR>\n" );
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document.write( "Alternatively, if you know calculus, the gradient, dy/dx of the general equation is 2ax+b. At the vertex, the gradient is zero, so put that into the equation and the x-value, and you get that 10a+b=0. Then put the values of the other point into the QUADRATIC general equation and use the fact that b=-10a, to find a.\r<BR>\n" );
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document.write( "Both methods are much the same. Take your pick.\r<BR>\n" );
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document.write( "jon. </SPAN>\n" );
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