Două laturi consecutive reprezintă lungimea, respectiv lățimea.
[tex]\it \mathcal{P}=2(L+\ell) \Rightarrow 120=2(L+\ell)\Big|_{:2} \Rightarrow 60=L+\ell \Rightarrow L+\ell=60\ \ \ \ \ (1)\\ \\ \\ \dfrac{L}{\ell}=\dfrac{9}{6} \Rightarrow \dfrac{L+\ell}{\ell}=\dfrac{9+6}{6} \Rightarrow\ \stackrel{(1)}{\Longrightarrow}\ \dfrac{60}{\ell}=\dfrac{^{4)}15}{6} \Rightarrow \dfrac{60}{\ell}=\dfrac{60}{24} \Rightarrow \ell=24\ cm\ \ \ \ (2)\\ \\ \\ (1),\ (2) \Rightarrow L+24=60 \Rightarrow L=60-24 \Rightarrow L=36\ cm[/tex]
