Răspuns :
1)
a+b=1275
a-419=b-56 |+56
a-419=b
Inlocuim b cu a-419=>
a+a-419=1275 |+419
2a=1694=>a=847,b=428
a+b=1275
a-475=b-56
a=b-56+475
a=b+419
b+419+b=1275
2b=1275-419=>b= 856/2=428
a=1275-428=847Verificam 847-475=428-56 =>372=372
2. a+b+c=12356
a=b+1821 => b=a-1821
a=c+586 => c= a-586
a+a-1821+a-586=12356
3a= 12356+2407=>a= 14763/3=4921
b=4921-1821=3100
c=4921-586=4335
4921+3100+4335=12356
a-475=b-56
a=b-56+475
a=b+419
b+419+b=1275
2b=1275-419=>b= 856/2=428
a=1275-428=847Verificam 847-475=428-56 =>372=372
2. a+b+c=12356
a=b+1821 => b=a-1821
a=c+586 => c= a-586
a+a-1821+a-586=12356
3a= 12356+2407=>a= 14763/3=4921
b=4921-1821=3100
c=4921-586=4335
4921+3100+4335=12356