Răspuns :
[tex]l_{\square}=\frac{40+80}{2}=20+40=60 \ (m); \\ P_{\square}=4l_{\square}=4 \cdot 60 \ m=\boxed{240 \ m}; \\ A_{\square}=l_{\square}^2=(60 \ m )^2=\boxed{3 \ 600 \ m^2}.[/tex]
Răspuns:
L=(40+80)/2=>L=60 m
P=4L=>P=4·60=>P=240 m
A=L²=>A=60·60=>A=3600 m²