[Toán 9] Hình học

H

hien_vuthithanh

♣/$S_{ABE}=2S_{ABC}$
$S_{AFE}=4S_{ABE}=8S_{ABC}$
♣/$S_{ADC}=S_{ABC}$
$S_{ECD}=3S_{ACD}$=3$_{ABC}$
♣/$S_{BCF}=3S_{ABC}$
$S_{BFD}=2S_{BCF}$=$6S_{ABC}$
\Rightarrow $S_{AFE}+S_{ECD}+S_{BFD}+S_{ABC}$=18$S_{ABC}$
\Leftrightarrow $S_{DEF}$=18$S_{ABC}$
 
You must log in or register to reply here.
Top Bottom