[tex] \frac{1}{3} [/tex] · x = [tex] \frac{x}{3} [/tex]
[tex] \frac{1}{2} [/tex] · [tex]( x- \frac{x}{3} ) = \frac{1}{2} [/tex]· [tex] \frac{3x-x}{3} = \frac{1}{2} [/tex]·[tex] \frac{2x}{3} = \frac{x}{3} [/tex]
20
[tex] \frac{x}{3} + \frac{x}{3} + 20 = x[/tex]
[tex] \frac{x}{3} + \frac{x}{3} + \frac{60}{3} = x [/tex]
[tex] \frac{2x}{3} + \frac{60}{3} = x [/tex]
[tex] \frac{2x+60}{3} = x [/tex]
[tex]3x = 2x + 60[/tex]
[tex]x = 60 [/tex]
In unele locuri trebuie aplificat, iti dai tu seama.
Sper ca te-am ajutat !