Răspuns :
x+2015-1018=1000
x+2015=1000+1018
x+2015=2018
x=2018-2015
x=3
Verificare:3+2015-1018=2018-1018=1000
x+2015=1000+1018
x+2015=2018
x=2018-2015
x=3
Verificare:3+2015-1018=2018-1018=1000
a+2015-1018=1000
a+997 = 1000
a= 1000 - 997
a = 3 (ani are papagalul Aurei )
a+997 = 1000
a= 1000 - 997
a = 3 (ani are papagalul Aurei )