The demand for video recorders has been estimated to linear and given by the demand relation QV = 145 – 3.2PV + 7M – 0.95PF – 39PM, where QV is the quantity of video recorders, Pf denotes the price of video recorder film, PM is the price of attending a movie, PV is the price of video recorders, and M is income. Based on the estimated demand equation we can conclude: