2016 Fermat Problem 16

If x = 18 is one of the solutions of the equation x^2 + 12x + c = 0, the other solution of this equation is

\textbf{(A)}\ x = 216\quad \textbf{(B)}\ x = -6\quad \textbf{(C)}\ x = -30\quad \textbf{(D)}\ x = 30\quad \textbf{(E)}\ x = -540

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