Systems Of Equations Word Problems

themadhatter1

1. Haha. Don't know how that slipped me.

2.
Ok, I think I understand this but, for the upper left one wouldn't it be 600=x₁+x₃ because the 2 outputs of the upper left junction are x₁ and x₃?

themadhatter1	1. Haha. Don't know how that slipped me. 2. Ok, I think I understand this but, for the upper left one wouldn't it be 600=x₁+x₃ because the 2 outputs of the upper left junction are x₁ and x₃?