Q9 of 23 Page 330

The co-ordinates of vertices of a triangle are (4, –3), (–5, 2) and (x, y); let us find the value of x and y, if the centroid of triangle is at origin.

Let the points of triangle be


A = (x1, y1) = (4, -3) and


B = (x2, y2) = (-5, 2) and


C = (x3, y3) = (x, y)


Centroid of triangle is origin hence G be the centroid G (0, 0)


Centroid of a triangle is given by


G =


Substituting values


⇒ (0, 0) =


Equate x-coordinate and y-coordinate


⇒ = 0 and = 0


⇒ x – 1 = 0 and y – 1 = 0


⇒ x = 1 and y = 1


Hence (x, y) is (1, 1)


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