document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=906403>Question 906403</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The graph of a function F is a parabola that has the x-intercepts 5 and 21. The function has a minimum value of -56. \r<BR>\n" );
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document.write( "The function is<BR>\n" );
document.write( "F(x) = ____ </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #549806 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=549806\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The graph of a function F is a parabola that has the x-intercepts 5 and 21. The function has a minimum value of -56.<BR>\n" );
document.write( "The function is<BR>\n" );
document.write( "F(x) =0.875(x-13)^2-56 <BR>\n" );
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document.write( "Vertex form of equation for a parabola: <BR>\n" );
document.write( "y=A(x-h)^2+k, (h,k)=coordinates of vertex<BR>\n" );
document.write( "k=-56(given)<BR>\n" );
document.write( "h=13 (midway between 5 and 21)(given x-intercepts)<BR>\n" );
document.write( "equation:y=A(x-13)^2-56<BR>\n" );
document.write( "solve for A using one of given points (5,0) on the curve<BR>\n" );
document.write( "0=A(5-13)^2-56<BR>\n" );
document.write( "64A=56<BR>\n" );
document.write( "A=56/64=0.875<BR>\n" );
document.write( "equation:y=0.875(x-13)^2-56 </SPAN>\n" );
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