Waves and vibration question need help professor never covered this i don't know what to do?

Two strings, of tension T and mass densities μ1 and μ2, are connected together. Consider a traveling wave incident on the boundary. Find the ratio of the reflected wave plus the energy flux of the transmitted wave equals the energy flux of the incident wave. [Hint: The energy flux of a wave (the energy density times the wave speed) is proportional to A2/v, where A is the amplitude and v is the wave speed]