you must give your full time job which paid 50000 year and you worked part time half

You must give up your full-time job, which paid $50,000 per year, and you worked part-time for half of the year. The average retail price of the cookbooks will be $30, and their average cost will be $20. Assume that the equation for demand is Q = 10,000 – 9,000P, where Q = the number of cookbooks sold per month P = the retail price of books. Show what the demand curve would look like if you sold the books between $25 and $35.