Let's look at the geometric characteristics of a cone. But first, please review the definition of Surface Area Of Three-Dimensional Shapes.

- A cone is a two dimensional circle with height; with height it becomes a three dimensional shape.
- The trick to determining the surface area of a cone is understanding the
base of the cone is a circle. The area of a circle is half the formula: Area Of A Circle. The area of a circle
formula is "pi" times radius × radius which equals πr
^{2}. - The second part of the formula is to compute the surface
area of the Cone above the base. Let us call
**L**the slant-Length. Slant-Length = L = distance between the cone tip and the base. The formula for the surface area of a Cone is πrL. - Special note, the Base, Radius of the base and Length of a Cone must be greater than zero.

**Surface Area Of A Cone Formula**

Formula = (Base) + (π × radius × Length) =

Formula = (πr^{2}) + (π × radius × Length) =

Formula = π × radius^{2} + π × radius ×
Length =

Formula = πr^{2} + πrL =

Image Of A Three Dimensional Cone