Replace the three forces acting on the plate by a wrench. Specify the magnitude of the force and couple moment for the wrench and the point P(y, z) where its line of action intersects the plate.
Given:
{ F }_{ A } = 80 Ib\quad a = 12 ft
{ F }_{ B } = 60 Ib\quad b = 12 ft
{ F }_{ C } = 40 Ib