ANSWER
4 units.
Step-by-step explanation
Triangle RQT is a right isosceles triangle.
This implies that:
RQ=RT=x.
Triangle RTS is also a right angle triangle with hypotenuse, RT=x.
Also, the side with length , 2√3 units is opposite to the 60° angle.
We use the sine ratio, to obtain:


Solve for x to obtain;

This gives us:

Therefore the value of x is 4 units.