Question

aflati A si B,stiind ca (a-5)*(b-7)=0.

Answer 1

(a-5)x(b-7)=0 => (a-5)=0 sau (b-7)=0
CAZ I :
(a-5)=0 => a=5
0x(b-7)=0 => b apartine {7,8,9,...}
CAZ II
(b-7)=0 => B=7
(a-5)x0=0 => a apartine {5,6,7,...}