Diagram attached. The spring is unstretched when theta = 0. Determine the theta for equilibrium. I'm not quite sure how to get started here. My prof said that we cannot assume that the tension in the 400 N force cable at A is equal to the tension at the spring close to fixed support C (because it isn't a frictionless pulley). If we could make this assumption, I'd have the answer! But we can't. Any suggestions? Thanks.