1. The problem statement, all variables and given/known data This is the circuit I'm working on: 2. Relevant equations My equations are: 4.64v=-200I1-800I3 4.64v=750I3+800I2 4.64v=-200I1-750I3 3. The attempt at a solution I should have a third unknown in each equation. I not seeing where I'm going wrong. I'm supposed to put this in a 3X3 matrix and have Excel solve for the simultaneous equations. Any help?