A charity organization had to sell a few tickets to their fundraiser just to cover necessary production costs. After selling 101010 tickets, they were still at a net loss of \$800$800dollar sign, 800 (due to the production costs). They sold each ticket for \$70$70dollar sign, 70. Let yyy represent the net profit (in dollars) when they have sold xxx tickets. Complete the equation for the relationship between the net profit and number of tickets sold.