Question

Doua numere naturale au suma 1279 si diferenta 51. Atunci numerele sunt .....

Answer 1

a+b=1279
a-b=51
a=b+51
b+51+b=1279
2b+51=1279
2b=1279-51
2b=1228
b=1228:2
b=614
a=614+51
a=665
proba: 665+614=1279
             665-614=51

Answer 2

$\text{Consideram numelere : a si b} \\ a+b=1279 \\ a-b=51 \\ \\ \text{Facem un sistem.} \\ \\ a+b=1279 \\ a-b=51 \\ ----- \\ 2a \ \ \ | \ \ 1330 \\ a=1330:2 \\ \bold{a=665} \\ \\ a-b=51 \\ 665-b=51 \\ \bold{b=614}$