Here, magnitude of first force, say, A = 70 N.
The magnitude of the second force, say, B = 50 N.
Angle θ between the two forces = 135 degrees.
So, the magnitude of the resultant is given by Eqn. (1.2) :
The magnitude of R = 49.5 N.
The direction is given by Eqn. (1.3):
Therefore, α = 45.0º (from the tables). Thus R makes an angle of 45º with 70 N force. That is, R is in North-west direction as shown in Fig. 1.9.