Force balance equations with moving base

[rihitz]

Homework Statement

Given:
AD=DC = 9m
P=78kN
S=25Kn
Angle alpha = 35 deg
A is static but B is movable

I need to solve forces on the bases A and B
I do not understand where do I mark the forces if there is a base that can move.

Homework Equations

The Attempt at a Solution

My attempt:

I am not sure whether there should be Bx or Ax.[/B]

 

[rihitz]

Is there only By on the base B? If so, is the B vector still calculateable with trigonometry, or the only force there will be By, without any Bx?