3c+2b+2f=583 (1)
2c+4b+1f=481 (2)
4c+2b+3f=771 (3)
c=?, b=?, f=?
relatia (3) - relatia (1)
1c / +1f=188
relatia (1)- relatia (2)
1c-2b+1f=102
inlocuim 1c+1f=188 si obtinem
188-2b=102
2b=188-102
2b=86
b=43 (o bluza 43 lei)
inlocuim pretul bluzei in relatia (1)
3c+2×43+2f=583
3c+86+2f=583
1c+2c+2f=583-86
1c+2(c+f)=497
1c+2×188=497
1c=497-376
1c=121 (un costum 121 lei)
c+f=188
f=188-c
f=188-121
f=67
verificarea o facem intr-una din relatii:
(3) 4×121+2×43+3×67=484+86+201=771
Raspuns: un costum: 121lei, o bluza: 43lei si o fusta:67 lei.
