,AB CD EF相交于O,EF⊥AB OG平分∠COF,OH平分∠DOG若∠AOC:∠DOH=8:28,求∠COH的大小

问题描述:

,AB CD EF相交于O,EF⊥AB OG平分∠COF,OH平分∠DOG若∠AOC:∠DOH=8:28,求∠COH的大小

因为∠AOC:∠DOH=8:28,所以设∠AOC=2x,∠DOH=7x设∠DOF=y因为OG平分∠COF,所以∠COG=1/2∠COF=1/2(∠COD-∠DOF)=1/2(180-y)因为OH平分∠DOG,所以∠DOH=1/2 ∠DOG=1/2(∠COD-∠COG)=1/2(180-(1/2(180-y))=...