document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=408857>Question 408857</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The function f (x) = 2x2 + 8x + c has a minimum value of &#8722;11.Find the value of<BR>\n" );
document.write( "c </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #287957 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=287957\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> given:<BR>\n" );
document.write( "f(x) = 2x^2 + 8x + c<BR>\n" );
document.write( "we know that it is a parabola that opens upwards (because of the positive coefficient associated with the x^2 term).<BR>\n" );
document.write( "Therefore, the vertex gives you the minimum.<BR>\n" );
document.write( ".<BR>\n" );
document.write( "x-coordinate of minimum:<BR>\n" );
document.write( "x = -b/(2a) = -8/(2*2) = -8/4 = -2<BR>\n" );
document.write( ".<BR>\n" );
document.write( "f(x) = 2x^2 + 8x + c<BR>\n" );
document.write( "-11 = 2(-2)^2 + 8(-2) + c<BR>\n" );
document.write( "-11 = 2(4) + (-16) + c<BR>\n" );
document.write( "-11 = 8 - 16 + c<BR>\n" );
document.write( "-11 = -8 + c<BR>\n" );
document.write( "-3 = c <BR>\n" );
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