What is the total area of a cylinder with a radius of 8cm and a height of 8cm?

Answer 1

I presume you mean total surface area of the cylinder:

Area = 2πr(r + h)

= 2π8(8 + 8)

= 256π cm2

~= 804.25 cm2

The cylinder consists of 2 circular disks at each end and the curved surface.

The area of each of the disks is πr2.

To work out the area of the curved surface, imagine cutting the cylinder from end to end and flattening out the edge; then it will be a rectangle with length the height of the cylinder and width the perimeter of the circular end. Thus its area is 2πrh

Thus the total surface area of the cylinder is:

area = πr2 + πr2 + 2πrh

= 2πr2 + 2πrh

= 2πr(r + h)