[tex]\frac{x-3y}{x+3y}=\frac{1}{5} \implies 5(x-3y)=x+3y[/tex]
[tex]\implies 5x-15y=x+3y[/tex]
[tex]\implies 5x-x=3y+15y[/tex]
[tex]\implies 4x=18y[/tex]
Inlocuim pe 4x in raportul care ne intereseaza:
[tex]\frac{4x+y}{4x-y}=\frac{18y+y}{18y-y}=\frac{19y}{17y}=\frac{19}{17}[/tex]