Question

aflati a,b ( a,b)= 3 a+b=21​

Answer 1

Explicație pas cu pas:

(a,b)=3=>a=3x si b=3y unde (x,y)=1

a+b=21=>3x+3y=21=>3(x+y)=21=>x+y=7

Avem cazurile:

x=1 y=6=>a=3 b=18

x=6 y=1=>a=18 b=3

x=3 y=4=>a=9 b=12

x=4 y=3=>a=12b=9