SA= (πr²) + (2πrh) + (πr²)
The lenght of the rectangle is equal to the circumference of the circle.
radius (r) = distance (length) from the center to the outer ring.
Volume of a Cylinder
the cylinder has 3 shapes, 2 circles and a rectangle. To get the surface area of a cylinder follows this formula:
SA = (Pi x r²) + (2 x Pi x r) + ( Pi x r²)
In class we had a an example question: the height is 10 and the radius is 5. The circumference is the length of the rectangle so you get the area of the 3 shapes and add them together to ge the Surface area.
SA = (3.14 x 25) + (2 x 3.14 x 5) + ( 3.14 x 25)
= 78.5 + 314 + 78.5