Three coplanar forces act at a point and keep the point in equilibrium. Two of the forces have magnitudes 10N due east and 15N due north respectively.
a. (a) Calculate the magnitude of the third force required for equilibrium.
b. (b) Determine the direction of this third force with respect to the eastward direction.
c. (c) Verify by component addition that the vector sum of the three forces is zero.