Răspuns :
Notam
x-nr
y-nr
---
x+y=931
x-y=y:3
x=931-y
931-y-y=y:3
931-2·y=y:3
931·3-2y·3=y
2793-6·y=y
y+6·y=2793
7·y=2793
y=2793:7
y=399
x=931-399
x=532
Notam
x-nr
y-nr
---
x+y=931
x-y=y:3
x=931-y
931-y-y=y:3
931-2·y=y:3
931·3-2y·3=y
2793-6·y=y
y+6·y=2793
7·y=2793
y=2793:7
y=399
x=931-399
x=532