If the origin is the centroid of a triangle ABC having vertices A(a, 1, 3), B(-2, b, -5) and C(4, 7, c), find the values of a, b, c.

Given: The coordinates of the A, B and C of the triangle ABC are (a, 1, 3), (-2, b, -5) and (4, 7, c) respectively. The centroid of the triangle is (0, 0, 0)


To find: the values of a, b, c


Formula used:


Centroid of triangle ABC whose vertices are A(x1, y1, z1), B(x2, y2, z2) and C(x3, y3, z3) is given by,



Here A(a, 1, 3), B(-2, b, -5) and C(4, 7, c)


Centroid of the triangle





On comparing:



a + 2 = 0


a = –2



b + 5 = 0


b = –5



c – 2 = 0


c = 2


Hence, values of a, b and c are -2, -5, 2


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