x/y=2/3 => 2y=3x => y=3x/2
=> (6x+y)/(x+3y)=(6x+3x/2)/(x+9x/2)
Aducem la acelasi numitor in paranteze si obtinem:
(12x/2+3x/2)/(2x/2+9x/2)=(15x/2)/(11x/2)
sa imparti la o fractie inseamna sa inmultesti cu inversa acesteia deci:
(15x/2)/(11x/2)=(15x/2)•(2/11x)=(2•15x)/(2•11x)=15/11
