Question

If r = 8 units and x = 8 units, then what is the total surface area of the cylinder shown above?

Answer 1

The surface area of a cylinder is the area of the top and bottom circle and the side of the cylinder, which is really a rectangle with the circumference of the circle for the length and x for the width.
So the formula is $2 \pi rh+2 \pi r^2$
Plug in r  and x into the equation;
$2* \pi *8*8 +2* \pi *8^{2}$
$128 \pi +128 \pi$
$256 \pi$
which is about 804.25 square units since it is an area.
Hope this helps.