Q11 of 35 Page 793

Two vertices of a triangle ABC are A(2, -4, 3) and B(3, -1, -2), and its centroid is (1, 0, 3). Find its third vertex C.

Since the centroid of a triangle


The points are A(2, -4, 3) and B(3, -1, -2), and its centroid is (1, 0, 3). And let its third vertex C(a,b,c).


Using the formula, we get




Equating it with the coordinates of centroid, we get



a = -2



b = -5


and,


c = 7


therefore, the point is (-2,-5,7)


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