Răspuns :
x-2012= 2013:2013
x-2012= 1
x= 1+2012
x= 2013
PROBA
2013:(2013-2012)= 2013
2013:1= 2013
2013= 2013
x-2012= 1
x= 1+2012
x= 2013
PROBA
2013:(2013-2012)= 2013
2013:1= 2013
2013= 2013