如图,两直线AB,CD相交于点O,OE平分∠BOD,如果∠AOC:∠AOD=7:11.若OF⊥OE,求∠COFhttp://hiphotos.baidu.com/%DC%F2%DC%DF%C8%F5%CB%AE/pic/item/d606b51d3a5e9134dab4bd95.jpg
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/03 10:52:17
![如图,两直线AB,CD相交于点O,OE平分∠BOD,如果∠AOC:∠AOD=7:11.若OF⊥OE,求∠COFhttp://hiphotos.baidu.com/%DC%F2%DC%DF%C8%F5%CB%AE/pic/item/d606b51d3a5e9134dab4bd95.jpg](/uploads/image/z/1051334-62-4.jpg?t=%E5%A6%82%E5%9B%BE%2C%E4%B8%A4%E7%9B%B4%E7%BA%BFAB%2CCD%E7%9B%B8%E4%BA%A4%E4%BA%8E%E7%82%B9O%2COE%E5%B9%B3%E5%88%86%E2%88%A0BOD%2C%E5%A6%82%E6%9E%9C%E2%88%A0AOC%3A%E2%88%A0AOD%3D7%3A11.%E8%8B%A5OF%E2%8A%A5OE%2C%E6%B1%82%E2%88%A0COFhttp%3A%2F%2Fhiphotos.baidu.com%2F%25DC%25F2%25DC%25DF%25C8%25F5%25CB%25AE%2Fpic%2Fitem%2Fd606b51d3a5e9134dab4bd95.jpg)
如图,两直线AB,CD相交于点O,OE平分∠BOD,如果∠AOC:∠AOD=7:11.若OF⊥OE,求∠COFhttp://hiphotos.baidu.com/%DC%F2%DC%DF%C8%F5%CB%AE/pic/item/d606b51d3a5e9134dab4bd95.jpg
如图,两直线AB,CD相交于点O,OE平分∠BOD,如果∠AOC:∠AOD=7:11.若OF⊥OE,求∠COF
http://hiphotos.baidu.com/%DC%F2%DC%DF%C8%F5%CB%AE/pic/item/d606b51d3a5e9134dab4bd95.jpg
如图,两直线AB,CD相交于点O,OE平分∠BOD,如果∠AOC:∠AOD=7:11.若OF⊥OE,求∠COFhttp://hiphotos.baidu.com/%DC%F2%DC%DF%C8%F5%CB%AE/pic/item/d606b51d3a5e9134dab4bd95.jpg
∵∠AOC:∠AOD=7:11,而∠AOC+∠AOD=180°
∴∠AOC=70°,∠AOD=110°,
∴∠BOD=∠AOC=70°,又∵OE平分∠BOD
∴∠BOE=35°,OF⊥OE,
∴∠FOE=90°,
∴∠AOF=180°-90°-35°=55°
∴∠COF=∠AOC+∠AOF=70°+55°=125°
∠AOC:∠AOD=7:11求出∠AOC=70°,∠AOD=110°,
∠AOC=∠BDO=∠BOE+∠DOE,因为∠BOE=∠DOE,所以∠BOE=35°,因为OF⊥OE,所以∠EOF=90°,所以∠AOF=180°-35°-90°=55°,∠COF=∠AOC+∠AOF=70+55=125°