Consider the following premises. t <-> r_3. ~q_17. t <-> q_17. Can we infer r_3 from them?
 From t <-> q_17 we can infer t -> q_17. From t -> q_17, ~q_17 we can infer ~t. Finally, from t <-> r_3, ~t we can infer ~r_3, which contradicts r_3. Therefore, the answer is no.