Q11 of 50 Page 220

Find the third vertex of triangle whose centroid is origin and two vertices are (2, 4, 6) and (0, –2, –5).

Given; The centroid is origin and two vertices are (2, 4, 6) and (0, –2, –5).

Let the third vertex be (x,y,z);


For a triangle the coordinates of the centroid is given by the average of the coordinates of its vertices.






∴ the third vertex is (−2, −2, −1).


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