Q3 of 77 Page 7


Find the third vertex of a triangle, if two of its vertices are at (-3, 1)and (0, -2) and the centroid is at the origin.

(3, 1)
SOLUTION:

Given, the two vertices of the triangle are (-3, 1), (0, -2).
Let the third vertex be (x, y)
Also given the centroid of the triangle = (0, 0)
∵ The centroid of the triangle =

⇒ -3 + x = 0, -1 + y = 0
∴ x = 3, y = 1

Third vertex = (3, 1)

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