Notam:
a=nectarine; b= piersici.
4a+6b=48
3a+9b=54
a=?; b=?
Rezolvare:
3a+9b= 54; 3a= 54-9b; a= ( 54-9b)/3; a= 9(6-b)/3; a= 3(6-b); a= 18-3b
Inlocuim pe a:
4(18-3b)+6b=48; 72-12b+6b=48; 6b= 24;
b=4 b= piersici, deci 1 kg piersici =4 lei;
3a+9b = 54; 3a+ 9x4= 54; 3a= 18;
a= 6 a= nectarine, deci 1 kg nectarine= 6 lei