Answer:
Option D. 18 cm
Explanation:
we know that
A centroid of a triangle is the point where the three medians of the triangle meet.
A median of a triangle is a line segment from one vertex to the mid point on the opposite side of the triangle.
The centroid divides each median in a ratio of 2:1
In this problem the centroid of triangle RST is the point X
so
![(RX)/(XW)=(2)/(1)](https://img.qammunity.org/2020/formulas/mathematics/high-school/unkf1qurusbbzdz9a18hj0lqtpdk91o2yp.png)
-----> equation A
-----> equation B
substitute equation A in equation B
![2XW+XW=27](https://img.qammunity.org/2020/formulas/mathematics/high-school/5jxbb5vwa8g07vu3nlwtchfcnczq7gqfmv.png)
Solve for XW
![3XW=27](https://img.qammunity.org/2020/formulas/mathematics/high-school/7flqmpke45ck8i06blgz3elijl3wbheh0g.png)
![XW=9\ cm](https://img.qammunity.org/2020/formulas/mathematics/high-school/ihktau7utghy7qqkatecuz59szj1uvd7vn.png)
Find the value of RX
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