Q22 of 184 Page 10

The coordinates of the centroid of a triangle and those of two of its vertices are A(3, 1), B(1, -3) and the centroid of the triangle lies on the x-axis. Find the coordinates of the third vertex C.

Given: A(3, 1) and B(1, -3)


To find: Find the coordinate of the third vertex C.



Let Assume C = (a, b)


Centroid on C



Therefore, G(1, 0) as it lies on x-axis


⇒ 4 + a = 3


⇒ a = -1


⇒ - 2 + b = 0


⇒ b = 2


Hence, C is (-1, 2)


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