0 1 12 3456789
:; & lt=
1.c2
. /0 12 34 2.3 4 5
& gt? & lt@
6 1
d 62 15063∶S△AHC = 14ac 2,S△CFB= 14BC2,S△A
BE= 14
AB2
,∴s78= 14ac2+ 14bc2+ 14ab2
=
14×2 AB2
= 12AB2=92
. Accelerated business collection and delivery system (adopted by the United States post office)
6 9△ABC:,; & ltAB= 10,BC=8,= & gt2AC,= & gt2