∠AOC+∠BOD = 180-45 = 135

OE and OF are divided equally ∠AOC and ∠DOB.

∠EOC = 1/2∠AOC∠FOD = 1/2∠BOD

∠EOC+∠FOD = 1/2(∠AOC+∠BOD)= 67.5

∠EOF =∠EOC+∠FOD+∠COD = 67.5+45 = 1 12.5