document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=923836>Question 923836</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose f(x) = (x-7)(x+4). \r<BR>\n" );
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document.write( "(a) For which values of x is the function f(x) positive? Enter your answer using inequalities. <BR>\n" );
document.write( " help (inequalities) \r<BR>\n" );
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document.write( "(a) For which values of x is the function f(x) negative? Enter your answer using inequalities. <BR>\n" );
document.write( " help (inequalities) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #560368 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=560368\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> f(x) = (x-7)(x+4) is a parabola that crosses the x axis at (-4,0) and (7,0), the equation can be rewritten as<BR>\n" );
document.write( "f(x) = x^2 -3x - 28<BR>\n" );
document.write( "note that the parabola crosses the y axis at (0,-28) and it opens upward<BR>\n" );
document.write( "a)  x < -4 or x > 7<BR>\n" );
document.write( "b)  -4 < x < 7 </SPAN>\n" );
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