来自路懿的问题
如图,△ABC中,AD是中线,AE是角平分线,CF⊥AE于F,AB=5,AC=2,则DF的长为______.
如图,△ABC中,AD是中线,AE是角平分线,CF⊥AE于F,AB=5,AC=2,则DF的长为______.
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2020-12-20 01:46
如图,△ABC中,AD是中线,AE是角平分线,CF⊥AE于F,AB=5,AC=2,则DF的长为______.
如图,△ABC中,AD是中线,AE是角平分线,CF⊥AE于F,AB=5,AC=2,则DF的长为______.
延长CF交AB于点G,∵AE平分∠BAC,∴∠GAF=∠CAF,∵AF垂直CG,∴∠AFG=∠AFC,在△AFG和△AFC中,∵∠GAF=∠CAFAF=AF∠AFG=∠AFC,∴△AFG≌△AFC(ASA),∴AC=AG,GF=CF,又∵点D是BC中点,∴DF是△CBG的中位...