I've sat around for hours and cannot get the right answer for this past exam question and my exam is in a week!
The diagram shows a sheet ABCDEFG of uniform thickness. An open envelope is formed by folding the sheet along CF and by glueing CD to CB and FE to FG.
Show that the distance of the centre of mass of the envelope from BG is 28/(8 + 3^0.5). You should ignore the mass of the glue.
Thank you so much in advance!