1. The problem statement, all variables and given/known data Calculate the value of R2 required to deliver 5W to RL if Vin equals 5V. 2. Relevant equations Vout=iRL P=Ri^2 3. The attempt at a solution I started by using KVL for the input loop, noting that current is going counter-clockwise: Input loop: iR2-Vin=0→R2=Vin/i I found i by using P=Ri^2: i=sqrt(5/50) =0.316A Then, I used i from above to solve for R2: R2=Vin/i =5/0.316 =15.8Ω The answer should be 23.1Ω according to the book (Engineering Circuit Analysis 8ed). Where did I go wrong? I have tried so many different approaches, but I can never get to the answer of 23.1Ω.