Answer:

Explanation:
see the attached figure to better understand the problem
we know that
A centroid of a triangle is the point where the three medians of the triangle intersect. The centroid divides each median in a ratio of

In this problem the point X is the centroid of the triangle RST
so

----> equation A

solve for RX
-----> equation B
equate equation A and equation B



we have

substitute

Substitute in equation A

