Please answer this vector question.

Question

A parallelogram has 3 of its vertices at A(4,2,3) B(8.-1,-4) and C(11,3,-2).

determine the coordinates of the 4th vertex D(x,y,z) if Bc=AD.

Answer 1

Note the typo in B, with a period instead of a comma

IF BC = AD, then C - B = D - A, so D = A + C - B = (4,2,3) + (11,3,-2) - (8.-1,-4) = (7, 6, 5)