Consider the following premises. u <-> q_9. q_9. u -> w. Can we infer ~w from them?
 From u <-> q_9 we can infer q_9 -> u. From q_9 -> u, u -> w we can infer q_9 -> w. Finally, from q_9 -> w, q_9 we can infer w, which contradicts ~w. Therefore, the answer is no.