(2014?丹东一模)如图,在平行四边形ABCD中,BE平分∠ABC交AD于点E,CF平分∠BCD交AD于点F,AB=3,AD=5

日期:2016-10-29 09:31:08 人气:1

(2014?丹东一模)如图,在平行四边形ABCD中,BE平分∠ABC交AD于点E,CF平分∠BCD交AD于点F,AB=3,AD=5

∵四边形ABCD是平行四边形,∴∠AEB=∠EBC,∵BE平分∠ABC,∴∠ABE=∠EBC,则∠ABE=∠AEB,∴AB=AE=3,同理可证:DF=DC=AB=3,则EF=AE+FD-AD=3+3-5=1.故选A.
    A+
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