Find the centroid of ΔABC whose vertices are A(– 1, 0), B(5, – 2) and C(8, 2)


First we need to calculate the coordinates of median


For coordinates of median AD segment BC will be taken


X = (m1x2 + m2x1)/ m1 + m2


= (1 × 8 + 1x 5)/1 + 1


= (8 + 5) /2


= 13/2


Y = (m1y2 + m2y1)/ m1 + m2


= (1x 2 + 1x (– 2))/2


= (0)/2


= 0 / 2 = 0


D(13/2,0)


The centroid of the triangle divides the median in the ratio 2:1


By section formula,


X = (m1x2 + m2x1)/ m1 + m2


= (2 × 13/2 + 1x (– 1))/2 + 1


= (13 – 1) /3


= 12/3 = 4


Y = (m1y2 + m2y1)/ m1 + m2


= (2x 0 + 1x 0)/2 + 1


= 0/3


= 0


G coordinate is (4, 0)


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