I'm really unsure how to start with this. The instructions said to find Vin such that Vout will be 0.5Vin. The only given is Vd = 0.7 and Rd = 5 ohms. I tried to do a KVL equation but then I don't know what the current is since Vin is not given.
Additional info: Diode model that is used is the constant voltage drop model with resistance of Rd=5 ohms and forward voltage of 0.7