When we are dealing with object that are in equilibrium well then we know a few things. They are not moving so there is no net force on them. This does not mean there is NO force on the object but that ...

Forces Up = Forces Down

Forces Left = Forces Right

Moments Clockwise = Moments Anti-Clockwise

If the problem is not clear to you balance these forces all the same and see what they deliver you with. It often gets easier after you have uncovered these 3 equilibrium equations.

As it is in question 6/7 of this section if there is forces left and none right then FL = 0