document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=103198>Question 103198</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you help with this? I was told I could substitute the given numbers to get the equation, but what equation would I use? <BR>\n" );
document.write( "Find the equation of the parabola (with horizontal axis of symmetry) containing the point (20,4) with vertex (4,2)<BR>\n" );
document.write( "Thanks! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #75093 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=75093\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> horizontal axis of symmetry means a basic parabola of x=y^2 which has a vertex at the origin\r<BR>\n" );
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document.write( "the offset of the vertex results in x=a(y-2)^2+4\r<BR>\n" );
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document.write( "using the point to find a gives 20=a(4-2)^2+4 ... 16=4a ... 4=a\r<BR>\n" );
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document.write( "so the equation is x=4(y-2)^2+4 ... or x=4y^2-16y+20 </SPAN>\n" );
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