Two vertices of a triangle are ( 2, -6 ,4) , (4, -2, 3) and its centroid is (8/2 , -1 , 3) , find the third vertex.
denote centroid as C and vertices as A,B,D
then C(x)= ( A(x)+B(x)+D(x) )/3
substitute for x coordinates of A,B and centroid to find D(x);
similarly find y,z,coordinate of vertex D........