a + b = 742 → suma
a : 13 = b ⇒ a = 13 × b
_____________________
a + b = 742
13 × b + b = 742
14 × b = 742
b = 742 : 14
b = 53
a = 742 - 53 ⇒ a = 689
Verific:
689 + 53 = 742 → suma celor doua numere
689 : 13 = 53 → al doilea numar ( sau numarul mic )