[SOLVED] Calculate Load Resistance 1. The problem statement, all variables and given/known data Find RL if PL is 90W. 2. Relevant equations PL= ((V^2)*(RL))/((RL+r)^2) 3. The attempt at a solution I calculated the internal resistance to be 5 Ohms on my circuit with a supply voltage of 100V So, 90W = ((100^2) * (RL))/((RL + 5)^2) From this equation how do I rearrage the formula to get the Load Resistance?