Replace the three forces acting on the plate by a wrench. Specify the magnitude of the force

Question:

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(x, y) where its line of action intersects the plate.
Units Used:
kN = 103N
Given:
FA = 500 N
FB = 800 N
FC = 300 N
a = 4 m
b = 6 m

FB Fc