Equilibrium in a simple structure

The structure shown below is made up of two$-$force members with frictionless pins at

each joint, and only one significant force at point $A.$ It is held in place against a wall

by a pin at point $B$ and a roller at point $C.$ One can solve it using particle and rigid

body equilibrium methods, without any additional structural equilibrium concepts.

$($a$)$ Calculate the magnitudes of the forces exerted on point A from members $AB$ and

$AC.$

$($b$)$ Draw a free body diagram of the whole three$-$member structure as a rigid body.

$($c$)$ Calculate the magnitude of the force acting on the structure at point $C.$