document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=171877>Question 171877</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The roots  of x^2+kx+9=0 are real and equal. What are the possible values of k??? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #127009 by </B><A HREF=/tutors/aboutme.mpl?userid=monika_p><B>monika_p(71)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=monika_p><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=127009\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The roots  of x^2+kx+9=0 are real and equal. What are the possible values of k???\r<BR>\n" );
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document.write( "If the roots are equal(double root) it means that discriminant of quadratic equation b^2-4ac=0<BR>\n" );
document.write( "general form of quadratic equation is ax^2+bx+c=0\r<BR>\n" );
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document.write( "in this case a=1   b=k  and c=9<BR>\n" );
document.write( "b^2-4ac=0 then:<BR>\n" );
document.write( "k^2-36=0<BR>\n" );
document.write( "(k-6)(k+6)=0<BR>\n" );
document.write( "k=6 or k=-6<BR>\n" );
document.write( "For k=6 or k= -6 given equation has real and equal roots\r<BR>\n" );
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