I find it easiest to first calculate the reaction forces at the left and right feet of the ladder  call these forces R_ A and R_B. You can do this by considering moments acting on the ladder acting about point A:
Sum of Moments at A = 0 = R_B x 2 m  W x 3 m x sin(theta)
This gives R_A, then R_B comes from sum of forces in ydirection = 0.
Now consider the right hand piece of the ladder  it has R_B acting upward, T (tension in the connecting rod) acting to the left, and a horizontal and vertical reaction force at the pivot at the top. Finding the vertical component of the force at the pivot is now trivial, and you can see that the horizontal component must be equal to T, though acting in the opposite direction. Now you can perform a sum of moments about B = 0 and determine a value for T.
