Position Vector r from Point A to the
Force Line of Action


For this problem, the position vector is drawn from point A to point E giving
r_{AE} = 6i  k
Another position could be used, such from A to D.
The force vector can be determined by multiply its magnitude with its unit directional vector. The location of point D and E is (8,8,2) and (6,0,5) respectively. The force vector is
F = F u_{DE}
= 3.191i  12.764j + 4.786k
Substituting into the cross product gives,
This determinate can be evaluated as,
M_{A} = 12.76i  25.52j  76.58k
