Răspunsuri

2014-05-31T18:17:44+03:00
X-lungimea drumului

1/2 din x= 1/2 * x= x/2 -in 1a zi

x-x/2=  (2x-x)/2= x/2-restul

2/5 din x= 2/5 * x= 2x/5 -in a2a zi

x/2 + 2x/5 +2 =x  aducem la acelasi numitor
5x+4x+20=10x
9x-20=10x
9x-10x=-20
-x=-20
x=20