Răspuns:
scriem in baza 10
a+10a+b=b+10b+a+20
11a+b=11b+a+20
scadem un a si un b
10a=10b+20
impartim totul la 10
a=b+2
dam valori
a=1 b=3
a=2 b=4
a egal 3. b egal 5
a egal 4. b egal 6
a egal 5. b egal 7
a egal 6. b egal 8
a egal 7. b egal 9
R: ab=35 46 57 68 79
