2r+3c=21000, 2r=21000-3c, r=(21000-3c)/2, 3r+2c=24000 inlocuim pe r din prima ecuatie inncea de a doua, 3(21000-3c)/2+2c=24000, numitor comun2
3(21000-3c)+4c=48000, 63000-9c+4c=48000, 5c=63000-48000=15000,
c=15000/5=3000 parale un colier, r=(21000-9000)/2=12000/2=6000 parale o rochie