Răspuns :
3x+y/2x+7y=1/5⇒5(3x+y)=2x+7y⇒15x+5y=2x+7y⇒15x-2x=7y-5y=13x=2y⇒xy=2/13
sucees
sucees
3x+y/2x+7y=1/5
3x+y•1=2x+7y•5
3x+y=10x+35y
3x-10x=35y-y
-7x=34y
X/y=34/-7