Răspunsuri

2014-03-07T19:40:28+02:00
A supra b =3 pe 7 =k de unde rezulta ca a=3k si b=7k
inlocuim in relatia 2a+5b=82 rezulta ca 6k+35k=82,unde k=2
a=3k =6
b=7k=14
2014-03-07T20:11:38+02:00
 \frac{a}{b}= \frac{3}{7}
2a+5b=82
 \frac{a}{b}= \frac{3}{7} ⇒a= \frac{3b}{7}
2* \frac{3b}{7} +5b=82
 \frac{6b}{7}+ \frac{35b}{7}=82
 \frac{41b}{7} =82⇒41b=574⇒b=14
a=\frac{3*14}{7} ⇒a=3*2⇒a=6