# a right hexagonal prism

• May 15th 2008, 09:24 PM
shilo
a right hexagonal prism
i have a right hexagonal prism
and i need to find the SA and the volume for it
what formula do i use?
a regualr prism formula?
thanks
my test is tomorrow in the morning
• May 15th 2008, 10:05 PM
TheEmptySet
Quote:

Originally Posted by shilo
i have a right hexagonal prism
and i need to find the SA and the volume for it
what formula do i use?
a regualr prism formula?
thanks
my test is tomorrow in the morning

The Volume is the area of the base multiplied by the height

$\displaystyle V=A_{base} \cdot h$

The area of a Regular hexagon(all sides and angles equal) with side length l is $\displaystyle A=\frac{3\sqrt{3}}{2}l^2$

The surface area is given by the formula

$\displaystyle S=2A_{base}+6lh$

where l is the side length of the hexagon and h is the height.

I hope this helps

Good luck.
• May 16th 2008, 06:58 AM
Soroban
Hello, shilo!

Quote:

i have a right hexagonal prism,
and i need to find the SA and the volume for it.
what formula do i use?

I assume your exam will not include such a sloppy question . . .
Code:

        * - *       *    A    *       |  * - *  |       |  |  |  |       |  |  |  | h       |  |  |  |       |  |  |  |       *  |  |  *         * - *

We know nothing about the hexagon.
We must be given its perimeter $\displaystyle P$, and its area $\displaystyle A.$
. . (or be given enough information so we can find $\displaystyle P$ and $\displaystyle A$.)

The height $\displaystyle h$ is perpendicular to the two hexagonal bases.

The surface area consists of the top and bottom: .$\displaystyle 2A$
. . and the lateral area: .$\displaystyle Ph$

Therefore, the total surface area is: .$\displaystyle \boxed{ SA \:=\:2A + Ph}$

The volume is (area of base) × (height): .$\displaystyle \boxed{V \:=\:Ah}$