1. The problem statement, all variables and given/known data Find the voltage and the current through R5 http://i.imgur.com/bL9AFVo.jpg?1 2. Relevant equations Thevenin's theorem. 3. The attempt at a solution http://i.imgur.com/Lz9k8l2.jpg?1 * To find Vth: 1- Open circuit R5. 2- Find the voltage at A and B by determining the current through R1, R2, R3 and R4 (Their Req=(R1+R4)//(R2+R3)=368.4 ohms 3- The current is equal to 0.24 A, hence the Vab=Vth=30V http://i.imgur.com/Lz9k8l2.jpg?1 * To find Rth (=Rab): 1- Open circuit R5 and short circuit the voltage source. 2- (R1+R4)//(R2+R3)=368.4 ohms My problem is here, does the wire (caused by short circuiting the source) cause short on (R1+R4)?