the function of quadratic is number4
The surface area of a right cylinder is the sum of the areas of the lateral face and the circular bases. The lateral face is really just a rectangle with the same height as the cylinder and a length equal to the circumference of the circular base.
If the radius of the base is

and the height is

, then the surface area of the cylinder is

You're given that the area is

and the radius is

, so you have
8 and 9 because 8 x 8= 64 and 9 x 9 = 81. Between 64 and 81 is 75.
-9(c+4)(c-4)
this is the answer to your question