perimetrul patrat= Pp; aria patrat Ap ; lp=latura patrat
perimetru dreptunghi=Pd ; aria dreptunghi=Ad
Pp=Pd
Ap=81m patrati
[tex]Ap= l^{2} , lp= \sqrt{81} =9[/tex]
Pp=4*l=4*9=36
Pp=Pd=36m
Pd=2*l+2*L
[tex]l= \frac{4}{5}*L [/tex]
[tex]2* \frac{4}{5}L+2*L=36 [/tex]
[tex] \frac{8}{5}L+2L=36 [/tex]
amplificam cu 5 si vom avea
8L+10L=180
18L=180
L=180:18
L=10m
[tex]l= \frac{4}{5}*10=8 [/tex] m
Ad=l-L=8*10=80m patrati
b) [tex]lp= \frac{3}{2}*10=15m [/tex]
[tex]Ap= 15^{2}=225 [/tex]
