Ans: C
Since the quadratic equation $x^2+kx+8k+36=0$ has equal roots, we have
Since the quadratic equation $x^2+kx+8k+36=0$ has equal roots, we have
$\begin{array}{rcl}
\Delta & = & 0 \\
(k)^2 – 4(1)(8k+36) & = & 0 \\
k^2 – 32k – 144 & = & 0 \\
(k+4)(k-36) & = & 0
\end{array}$
$\therefore k=-4 \ \text{or} \ k=36$.
