过A作AG⊥BC于G,过E作EH⊥ (BC于H,.
△ADC~△EHC (AAA).
∴CE:CA=EH:AG=2:3.----->EH=(2/3)AG.
S△ABC=(1/2)BC*AG=108.
即.BC*AG=216.(1).
S△CDE=(1/2)DC*EH=(1/2)*(1/2)BC*(2/3)AG.
=(1/6)BC*AG.
=(1/6)*216.
=36 (平方厘米) ----即为所求.
过A作AG⊥BC于G,过E作EH⊥ (BC于H,.
△ADC~△EHC (AAA).
∴CE:CA=EH:AG=2:3.----->EH=(2/3)AG.
S△ABC=(1/2)BC*AG=108.
即.BC*AG=216.(1).
S△CDE=(1/2)DC*EH=(1/2)*(1/2)BC*(2/3)AG.
=(1/6)BC*AG.
=(1/6)*216.
=36 (平方厘米) ----即为所求.