Use cavalieri’s principle to calculate the exact volume of an oblique cylinder with a height of 10 meters and a circular base with a radius of 8 meters

The area of a rectangle is 10 cm^2. one side of the rectangle is x cm. express the perimeter of the rectangle in terms of x and show that this rectangle cannot have a perimeter of 12 cm. the perimeter of the rectangle in terms of x is __ cm