Consider the following premises. q_9. q or ~q_9. q -> q_9. Can we infer q from them? If possible, name the inference rules being used at each step.
 From q or ~q_9 we can infer q_9 -> q via rewriting. From q -> q_9, q_9 -> q we can infer q <-> q_9 via biconditional introduction. From q <-> q_9 we can infer q_9 -> q via biconditional elimination. Finally, from q_9 -> q, q_9 we can infer q via modus ponens. Therefore, the answer is yes.