In a certain region, about 7% of a city's population moves to the surrounding suburbs each year, and about 5% of the suburban population moves into the city. In 2010, there were 800,000 residents in the city and 500,000 in the suburbs. Set up a difference equation that describes this situation, where x0 is the initial population in 2010 Then estimate the populations in the city and in the suburbs two years later, in 2012. (Ignore other factors that might influence the population sizes.)