Răspuns :
a-b=(a+b):3=636:3=212=>a=b+212
a+b=636
b+212+b=636
2b=424
b=212
a=424
a+b=636
a-b=636:3
a-b=212
b=(636-212):2
b=212
a=212×2
a=424
proba 424+212=636
424-212=212
a-b=(a+b):3=636:3=212=>a=b+212
a+b=636
b+212+b=636
2b=424
b=212
a=424
a+b=636
a-b=636:3
a-b=212
b=(636-212):2
b=212
a=212×2
a=424
proba 424+212=636
424-212=212