Q10 of 77 Page 7


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

(3, 1)

SOLUTION:
Let the third vertex of the triangle be C(x, y) and the other vertices are A(-3, 1) and B(0, -2).

Coordinates of 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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