Răspunsuri

2014-09-23T16:48:09+03:00

x/y=2/5,2x+y=81,y=81-2x
5x=2y,y=5x/2,5x/2=81-2x,5x=162-4x
9x=162,x=18

y=81-2x18=81-36=45

e cel mai bun rezultat?