Răspunsuri

2014-08-08T11:37:58+03:00
Ma=(a+b)/2= 7,5

a+b=2*7,5
a+b=15

a=1/4 *b

a=b/4

b/4 +b=15  aducem la acelasi numitor

b+4b=15*4
5b=15*4

b=15*4/5
b=3*4=12

a=12/4=3