Răspuns:
Explicație pas cu pas:
x/y = 2/5
x = 2y/5
2x + y = 4y/5 + y = 4y/5 + 5y/5 = 9y/5
y - x = y - 2y/5 = 5y/5 - 2y/5 = 3y/5
9y/5 : 3y/5 = 9y/5 * 5/3y = 3
Salutare ;)
x/y=2/5=2k/5k(am amplificat cu k)=> x=2k ; y=5k
2x+y/y-x=2×2k+5k/5k-2k=4k+5k/3k=9k/3k=9/3(am simplicat cu k)=3/1(am simplificat cu 3)=3
Baftă la mate :3