These equations exhibit a symmetry that may be used to write the equations in the rearranged from by inspection . In (4.1) the coefficient of v1 is the sum of conductanc of the element connecting node1 to node2. The same statement holds for (4.2) the numbers 1 and 2 are interchanged. Thus node 2 plays the role in (4.2) of node 1 in(4.1). That is, it is the node at which KCL is applied. In each equation the right-hand side is the current from a current from a current source which enters the corresponding node.