Question

已知∠AOD=∠BOC=90°,且∠AOB=4∠COD,则∠COD=

Answer 1

已知∠AOD=∠BOC=90°,且∠AOB=4∠COD,则∠COD=?

已知∠AOD=∠BOC=90°,∠AOB=4∠COD

∠AOB+4∠COD=360°-∠AOD-∠BOC

∠AOB+4∠COD=360°-90°-90°

∠AOB+4∠COD=180°

∠AOB=180°/5*4=144°

∠COD=∠AOB/4=144°/4=36°

答：

∠COD=36°