The figure shows the free body diagram of the beam. The reaction forces at C are C subscript x and C subscript y directed horizontally to the right and vertically upwards respectively. A 75 kilo newton load acts on the beam 2.5 meters from point C. The force along the support rod directed away from the point B is F subscript 1 at an angle of 35 degrees with the horizontal.

Begin by considering the equilibrium of beam BC.

Draw the free-body diagram for beam BC. Note that member (1) is a two-force member.

The equilibrium equations for beam BC are:

MC=-(75 kN)(2.5 m)      -(5.0 m) F1 sin(35.0)=0Fx=Cx- F1 cos(35.0)=0Fy=Cy-75 kN-F1 sin(35.0)=0