The co-ordinates of mid-points of sides of a triangle are (1, 2), (0, –1) and (2, –1). Find its centroid. -Maths 9th

1 Answer

Answer :

ABCD is a parallelogram, if the mid-points of diagonals AC and BD have the same co-ordinates (∵ Diagonals of a parallelogram bisect each other)Co-ordinates of mid-point of AC are \(\bigg(rac{a+2}{2},rac{-11+15}{2}\bigg)\) = \(\bigg(rac{a+2}{2},2\bigg)\)Co-ordinates of mid-point of BD are \(\bigg(rac{5+1}{2},rac{b+1}{2}\bigg)\) = \(\bigg(3,rac{a+2}{2}\bigg)\)Here, \(rac{a+2}{2}\) = 3 and 2 = \(rac{b+1}{2}\) ⇒ a = 4, b = 3.

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