Dau coroana la cel mai rapid raspuns

(3x-5y)/(2x+3y) = 2/3
⇔ 3·(3x-5y) = 2·(2x+3y)
⇔ 9x-15y = 4x+6y
⇔ 9x-4x = 6y+15y
⇔ 5x = 21y