Answer:
8
Explanation:
Two triangles are congruent if their corresponding sides are equal in length, and their corresponding angles are equal in measure. Having this in mind:

Where:

So, we will have the next equation:

Solving for v:
Subtract 3v from both sides:

Add 6 to both sides:

Divide both sides by 4:

Finally, replacing the value of v in QS and TV:

どういたしまして!