Mark the correct alternative in the following:

A plane meets the coordinate axes at A, B, C such that the centroid of ΔABC is the point (a, b, c). If the equation of the plane is then k =


A plane meets the co - ordinate axes at A, B, C such that the centroid of ΔABC is the point (a, b, c).


Let, the co - ordinates of the point A (α, 0, 0), B (0, β, 0) and C (0, 0, γ).


According to the centroid formula,








We know the intercept form of a plane is given as,



if the plane makes intercepts at (p, 0, 0), (0, q, 0) and (0, 0, r) with the x - , y - and z - axes respectively.


Here, p=α=3a, q=β=3b and r=γ=3c


So, the equation of the plane is,




Equation of the given plane is



On comparing, we get, k=3.

1