Linear Algebra and Its Applications · Problem 2.5.7
Vector Spaces — Gilbert Strang
Mathematics · graphs-and-networks
Problem
If that second graph represents six games between four teams, and the score differences are b1,…,b6, when is it possible to assign potentials x1,…,x4 so that the potential differences agree with the b's? You are finding (from Kirchhoff or from elimination) the conditions that make Ax=b solvable.