Given:
In triangle XYZ, P is the centroid of triangle XYZ, YP = 8, QP = 5, YZ = 10.
To find:
The measure of median YS.
Solution:
We know that a centroid divides a median in 2:1.
P is the centroid and YS is the median. So,
![YP:PS=2:1](https://img.qammunity.org/2022/formulas/mathematics/high-school/97coru4857oxlkfw27gwdx8kk1d3ji1wkl.png)
Let the measure of YP and PS are 2x and x.
It is given that the measure of YP is 8.
![2x=8](https://img.qammunity.org/2022/formulas/mathematics/high-school/m0f5ezpa7zgxorbuul1rqsh35ycfkseyxo.png)
![x=(8)/(2)](https://img.qammunity.org/2022/formulas/mathematics/high-school/1cig0c3shmla69m9z3dehk1kxfrjslxqia.png)
![x=4](https://img.qammunity.org/2022/formulas/mathematics/high-school/lp82zoco0xlpxlhep3s8xzw5somhig1a8c.png)
![PS=4](https://img.qammunity.org/2022/formulas/mathematics/high-school/6ce03gedw39z084ug3zgnr309x0jjdw2sd.png)
Now, the measure of YS is:
![YS=YP+PS](https://img.qammunity.org/2022/formulas/mathematics/high-school/2pct5zoaqa8tvzibz218gig2ihrpqjxjih.png)
![YS=8+4](https://img.qammunity.org/2022/formulas/mathematics/high-school/6y90lszuph61vgyyqx57ha9f96u7izd4mf.png)
![YS=12](https://img.qammunity.org/2022/formulas/mathematics/high-school/ilou5k1sw9xptdlgm0grmsq1rnujgwt9q8.png)
The measure of median YS is 12 units. Therefore, the correct option is (a).