What digits can you put in the boxes to make the greatest possible product? What does it can you put in the boxes to make the smallest possible product? Use the digits 1-9 at most one time each

the answer, i believe is y-8=1(x+4)

the cost function, c(x), is the total cost of manufacturing x units of the product. how many units must the company produce and sell if they wish to make a b. if the company produces and sells 2000 units, would they obtain a profit or loss?