Q19 of 184 Page 10

Two vertices of a triangle are (1,4) and (5,2). If its centroid is (0,-3), find the third vertex.

Let the third vertex of a triangle be(x,y)


Here, x1 = 1, x2 = 5, x3 = x


and y1 = 4, y2 = 2, y3 = y


and the coordinates of the centroid is (0, -3)


We know that






⇒ 6 + x = 0 and 6 + y = -9


⇒ x = -6 and y = -15


Hence, the third vertex of a triangle is (-6, -15)


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