1. The problem statement, all variables and given/known data The problem is to find the current in the 25 ohm resistor (left side) http://imgur.com/a/luKCW [Image inserted by moderator] 2. Relevant equations KCL KVL ohms law (v=IR) 3. The attempt at a solution My attempt at the solution was to add both power sources together (-5v(-5v because the source is - +) and 15v). Then using ohms law, I could find current by dividing voltage (10) by resistance (25) to get .4A. However, this is wrong. I was told that I am not allowed to add the voltages together because there is a resistor between them (10 ohm resistor between the 2 power sources). The final answer is -.4A but I am completely clueless how to come up with this answer if I cannot add the sources together. I have found I2(top right of picture) to be -1.5A and i3 (bottom right of picture) to be -.5A but i'm not sure if those will be helpful in finding the current in just the 25 ohm side.