I don't have any more information. We work just with variables, no numbers. Need to find current trough Rp. Tried with node potentials, but can't get solution. Maybe use superposition - Vi1 = 0 and find part of Ip1 and then use Vi2= 0 and get Ip2, so Ip = Ip1 + Ip2. I study physics, so we rarely use real numbers, just get equations and relations.
Thanks