Question

P is the centroid of triangle MNO. MP=14x+8y. write expressions to represent PR and MR number 22 on sheet

Answer 1

• PR = 7x +4y
• MR = 21x +12y

Explanation:

The centroid is 1/3 the distance from the side to the opposite vertex. Hence ...

... PR = (1/3)(MP + PR)

... 3PR = MP + PR . . . . . . multiply by 3

.. 2PR = MP . . . . . . . . . . . subtract PR

... PR = MP/2 = (14x +8y)/2 . . . . . divide by 2, substitute for MP

... PR = 7x +4y

Of course, MR = MP + PR, so ...

... MR = (14x +8y) + (7x +4y)

... MR = 21x +12y