...

The second problem is a little trickier.

I'm sure I'll be setting up the equilibrium equations and solving them as a system, with the obvious AB = 2AD = 2AC substitution that they hand you, but expressing the equations as a function of d? Should that even be part of the strategy? Let me show you what I have for equilibrium:

The z angles are the angles between AC and AD vectors and the xy plane. These are also the angles used in the first trig factors in my x and y sums. The 71.57 and 108.435 are the angles AC and AD and the positive y axis, and the 198.435 and 161.565 are between the vectors and positive x axis.

But I have no strategy from here. I'm going to spend more time tomorrow on it but any thoughts of yours in the meantime would be very helpful. I think in the meantime I'm going to try to balance the equations without worrying about d, and if i can do that while satisfying AB = 2AD = 2AC, maybe it'll just work out.

thanks again