I've found that angle BDE is 122°, but I don't know how to find BOE. I know that BO and OE are the radii, but is there a way to prove that DE and BD are of equal length? And even if I do find angles DBE and DEB, how do I find BOE? I am rather confused. Or is there a way to use the alternate segment theorem?

Any help would be greatly appreciated. Thank you in advance.