document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1118965>Question 1118965</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find all the values of x (if any) where the tangent line to the graph of the given equation is horizontal.\r<BR>\n" );
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document.write( "y = 4x^2 + 13x + 13\r<BR>\n" );
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document.write( "A. 6.5\r<BR>\n" );
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document.write( "B. -1.63\r<BR>\n" );
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document.write( "C. 0\r<BR>\n" );
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document.write( "D. 6.5\r<BR>\n" );
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document.write( "E. 1.63 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #734391 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52781)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=734391\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Exactly at the vertex of the parabola:  x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-b%2F%282a%29 ALIGN=MIDDLE  ALT=\"-b%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-13%2F%282%2A4%29 ALIGN=MIDDLE  ALT=\"-13%2F%282%2A4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = -1.625.\r<BR>\n" );
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document.write( "Option B in your list.\r<BR>\n" );
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