How to win if somebody feeds badly?

Hey all, this isn't me saying "my team is so bad and they feed!!!"

But has anybody got any idea how you are supposed to win a game if somebody is feeding really badly ?. For instance, i played a game yesterday, i was ADC, me and morgana were doing good in botlane, pushed in the wave varus didn't stand a chance nor the sup, only problem is the jungler and mid would gank us pretty often. Believe Kata was something like 7/0 pretty early on from constant kills on our jungler and mid.

Im not posting this to complain about my team but has anybody found a legitimate way to fix that kind of situation?.