Edexcel M2 Centre of mass hanging problem

https://ca99c64778b62ba7e7b339967029e090c5733c3a.googledrive.com/host/0B1ZiqBksUHNYOXdJSDFGUUZPRUE/June%202014%20(R)%20QP%20-%20M2%20Edexcel.pdf

June 2014R question 4b.)

I have correctly calculated the answer to part a.) x=3

Need help desperately on this one.

@Zacken
@ghostwalker

You know the angle the vertical makes with AB, so draw that in. G lies on that line, so mark it somewhere reasonable, and drop a perpendicular to AB, meeting it at Y way.

Now consider the triangle AGY to find AY, and hence distance from DC

I think I am missing something with the concept of centre of mass. Its my weakest topic and something I'm going to pay the most attention to between now and friday.

imgur.com/QXHhHO0

No, the vertical won't go through the CofM of the triangle, nor the CofM of the square.

It will go through the CofM of the entire lamina (G), and be at 25 degrees to AB.

thats what I thought initially, I just deceived myself with the diagram haha.

Thanks for your help, I quickly realised that I could calculate the co-ordinate of yBAR of the lamina, and use this to solve for the y co-ordinate of the square.