The higher video price feeds back into the movie ticket market, causing demand to shift from DM to D’M and the price of movies to increase from $6.35 to $6.75.
This continues until a general equilibrium is reached, as shown at the intersection of D*M and S*M in (a), with a movie ticket of $6.82, and the intersection of D*V and SV in (b), with a DVD price of $3.58.