Answer
Given $\triangle RST\cong\triangle RVU$, it follows that $\triangle RSU\cong\triangle RVT$, according to method SAS.
Work Step by Step
Given $\triangle RST\cong\triangle RVU$, we can deduce that
1) $\overline{RS}\cong\overline{RV}$
2) $\angle S\cong\angle V$
3) $\overline{ST}\cong\overline{VU}$
Since $\overline{ST}\cong\overline{VU}$, it follows that $$\overline{ST}+\overline{TU}\cong\overline{VU}+\overline{TU}$$$$\overline{SU}\cong\overline{TV}$$
Considering $\triangle RSU$ and $\triangle RVT$, we have
1) $\overline{SU}\cong\overline{TV}$
2) $\angle S\cong\angle V$
3) $\overline{RS}\cong\overline{RV}$
Therefore, according to method SAS, $\triangle RSU\cong\triangle RVT$
