% When R=Ra then i=ia: Ra = 12; ia = 0.5106; % When R=Rb then i=ib Rb = 6; ib = 0.7164; A = [1 -ia; % 1 -ib]; % % Eqn 5.9-6 b = [Ra*ia; % Rb*ib]; % X = A\b; Vt = X(1) % Open Circuit Voltage Rt = X(2) % Thevenin Resistance

Figure 5.9-5 MATLAB file used to calculate the open-circuit voltage and the Thevenin resistance.