a+b=326
b+c=285 => b=285-c
a+c=353 => c=353-a
b=285-(353-a)
b=285-353+a
b=a-68
a+a-68=326
2a=326+68
2a=394
a=394:2
a=197
197+c=353
c=353-197
c=156
b+156=285
b=285-156
b=129
Facem verificari pentru a ne asigura ca am obtinut rezultate bune:
197+129=326
129+156=285
197+156=353