You land a sweet graphic design job after college. Because of your calculus prowess, you are assigned to the project of creating a rectangular poster, which is to contain 50 in^2of printing with a 4-inch margin top and bottom and a 2-inch margin left and right.

a. Express the dimensions of the sheet of paper that will minimize the amount of materials used. Hint: use area formula for both inner and outer rectangles; perimeter is irrelevant here.

b.Don't do the mathrather give a brief explanation how you would determine it's the cheapest and not the most expensive.