The problem is as follows:
The figure from below shows a golden square plate hanging from a wooded ceiling, the plate sides are $\textrm{ABCD}$. It is known that all sides are equal to $80\,cm$. The length between $BO=10\,cm$. Given these conditions, find the angle $\theta$.
The alternatives in my book are as follows:
$\begin{array}{ll} 1.&16^{\circ}\\ 2.&30^{\circ}\\ 3.&53^{\circ}\\ 4.&37^{\circ}\\ 5.&45^{\circ}\\ \end{array}$
Does it exist a way to solve this problem without much fuss?. I've attempted to apply the equilibrium condition on torques, but I'm confused exactly how it can be done or where exactly should it be applied the torque. Can someone help me with this?
I thought that the square could had been divided between two triangles and use the barycenter as the gravitational center and use this fact as the divided weight of the square plate but I came confused on how to use the distance from that center to the torque.
All and all can someone help me here?. How exactly should I find the requested angle?.
Hint:
Center of gravity $(F)$ will lie just below the point of suspension $(E)$.
Now, you got many right angled triangles. After some angle chasing, you will have $\angle EFG=\theta$.