Question

如图,在△ABC中,AO为角平分线,DE⊥AB于点E,DF⊥AC于F,AB=10厘米,AC=8厘米,DE=4厘米,求△A

Answer 1

∵AD平分∠BAC,DE⊥AB,DF⊥AC,

∴DE=DF=4㎝,

∴SΔABC=SΔABD+SΔADC

=1/2AB×DE+1/2AC×DF

=20+16

=36平方厘米.