1. The problem statement, all variables and given/known data http://www.wifstrand.se/albert/stuff/p6.5-9.png [Broken] I'm stuck with finding v_o1 (voltage over the 10kohm resistor when all sources but the 3 V source, which I've labeled v_1, is set to zero); seems like it should be really simple but I'm missing an equation. 2. Relevant equations http://www.wifstrand.se/albert/stuff/p6.5-9-superpos.png [Broken] Nodal analysis for this figure gives (v_a - 3)/8000 + (v_a - v_o1)/24000 = 0 3. The attempt at a solution I have two unknown variables but I can't figure out what the second equation would be. The answer given in the initial problem statement suggests that v_a = 2 V and v_o1 = -1 (since a_1 = v_01 * v_1 = (-1) * 3 = -3) which satisfies the equation above but naturally I'd like to know what I'd need to solve it. I can see that v_a - v_01 - 3 = 2 - (-1) - 3 = 0 but I'm not sure how to find that expression systematically and if it corresponds to KVL somehow.