Notăm cele două numere cu a și b.
[tex]\it \left.\begin{aligned} \it a\ \ |\rule{20}{0.8}|\rule{20}{0.8}|\ \ \ \ \ \ \ \ \ \ \ \ \ \ \\ \\ b\ \ |\rule{20}{0.8}|\rule{20}{0.8}|\rule{20}{0.8}|\rule{20}{0.8}|\end{aligned}\right\}\ 420\\ \\ \\ Avem\ 6\ segmente\ egale.\\ \\ 420:6=70\ (un\ segment)\\ \\ a=2\times70=140\\ \\ b=4\times70=280[/tex]
Sau:
[tex]\it \dfrac{a}{2}=\dfrac{b}{4}\ \Rightarrow b=\dfrac{4a}{2} \Rightarrow b=2a\ \ \ \ \ \ (1)\\ \\ \\ a+b=420\ \Rightarrow \ b=420-a\ \ \ \ \ \ (2)\\ \\ \\ (1),\ (2) \Rightarrow 2a=420-a\bigg|_{+a} \Rightarrow 3a=420\bigg|_{:3} \Rightarrow a=140\ \ \ \ \ \ (3)\\ \\ \\ (1),\ (3) \Rightarrow b=2\cdot140 \Rightarrow b=280[/tex]
