Respuesta :

Given:

The figure of a triangle LMN.

P is the centroid of triangle LMN.

To find:

14. Find the value of PN if QN=30.

15. Find the value of PN if QN=9.

Solution:

We know that the centroid in the intersection of medians of a triangle and centroid divides each median in 2:1.

Since P is the centroid it means NQ is the median from vertex N. It means P divides the median NQ in 2:1. So, PN:PQ=2:1.

14. We have QN=30.

[tex]PN=\dfrac{2}{2+1}QN[/tex]

[tex]PN=\dfrac{2}{3}(30)[/tex]

[tex]PN=2(10)[/tex]

[tex]PN=20[/tex]

Therefore, the value of PN is 20 when QN=30.

15. We have QN=9.

[tex]PN=\dfrac{2}{2+1}QN[/tex]

[tex]PN=\dfrac{2}{3}(9)[/tex]

[tex]PN=2(3)[/tex]

[tex]PN=6[/tex]

Therefore, the value of PN is 6 when QN=9.