document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=103792>Question 103792</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0030565111/algebrahomeworkh>Precalculus A GRAPHING APPROACH</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> My question is if the vertex of f(x)=-x^2+bx+8 has y-coordinate 17 and is in the second quadrant, find b. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #75450 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=75450\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> vertex=(h,k)=(h,17)<BR>\n" );
document.write( "-(x-h)^2+17=-x^2+bx+8<BR>\n" );
document.write( "We need a -9 to add to 17 to give 8. a has to be negative to give -x^2. h must be negative so that the vertex can be in the 2nd quadrant. <BR>\n" );
document.write( "h=-3<BR>\n" );
document.write( "-(x+3)^2=-(x^2+6x+9)+17 <BR>\n" );
document.write( "=-x^2-6x-9+17<BR>\n" );
document.write( "=-x^2-6x+8<BR>\n" );
document.write( "b=-6 Ans.<BR>\n" );
document.write( "Ed<BR>\n" );
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