a) 12²=144cm²
b)A'E/AA'=1/4⇒EA/A'A=3/4⇒EA=(3/4)*12=9cm
ABFE dreptunghi, latimea 12 cm inaltimea 9 cm....Perim=2(9+12)=2*21=42cm
c)
perimBEG=2BE+GE (BEG este isoscel cu baza EG)
BE=√(AB²+AE²)=√(12²+9²)=15cm
EG=12√2 (diag de patrat)
Perim=2*15+12√2=(30+12√2)cm