Question

Dacă ab+ba=165,determinati valoarea expresiei a+b.

Answer 1

$ab+ba=165$ => $(descompunem \ nr \ in \ baza \ 10) \ 10a+b+10b+a=165$ => $11a+11b=165$ => $11(a+b)=165$ => $a+b=\frac{165}{11}=15$