Răspuns :
L= 3l
Aria= L*l
675 = 3l*l
3l^2 = 675
3l = V675
3l = 15V3
l = 15V3/3
l = 5V3 cm
L = 5V3*3 = 15V3 cm
Perimetrul = 2(L+l) = 2*(15V3+5V3) = 2*20V3 = 40V3 cm
[tex]\it L= 3\ell\\ \\ \mathcal{A}=675\Rightarrow L\cdot\ell=675\Rightarrow 3\ell\cdot\ell= 675|_{:3} \Rightarrow \ell\cdot\ell=225 \Rightarrow \ell\cdot\ell=15\cdot 15 \Rightarrow\\ \\ \ell=15\ cm \\ \\ L=3\cdot15=45\ cm\\ \\ \mathcal{P}=2(L+\ell)=2(45+15)=2\cdot60=120\ cm[/tex]