Answer
Proof for the problem:
1. $\overline{SR}\cong\overline{SV}$ (1. Given)
2. $\overline{RT}\cong\overline{VT}$ (2. Given)
3. $\overline{ST}\cong\overline{ST}$ (3. Identity)
4. $\triangle RST\cong\triangle VST$ (4. SSS)
Work Step by Step
1) First, it is given that $\overline{SR}\cong\overline{SV}$
2) It is also given that $\overline{RT}\cong\overline{VT}$
3) By identity, we find that $\overline{ST}\cong\overline{ST}$
Now we see that all 3 sides of $\triangle RST$ are congruent with corresponding 3 sides of $\triangle VST$.
So we would use SSS to prove triangles congruent.
Now we would construct a proof for the problem:
1. $\overline{SR}\cong\overline{SV}$ (1. Given)
2. $\overline{RT}\cong\overline{VT}$ (2. Given)
3. $\overline{ST}\cong\overline{ST}$ (3. Identity)
4. $\triangle RST\cong\triangle VST$ (4. SSS)