1. The problem statement, all variables and given/known data http://img526.imageshack.us/img526/4890/asdny3.jpg [Broken] *Length of each side of the square is 3. *Length of DP = Length of BQ = Length of GR = 1 Calculate [tex]\theta[/tex], the angle that is made between the surface of PQR and the surface of CGHD 2. Relevant equations No relevant equation was given for me, but I'm going to throw out some that may help. *Law of Cosines *Dot Product 3. The attempt at a solution I do not have a single clue of what to do. Can anyone start me off somehow, and tell me what I should be initially looking for in order to find the angle between the surfaces?