Posted by **dull** on Sunday, July 14, 2013 at 10:26am.

Find the surface area of a triangular pyramid with b =4 cm, h= 8.2 cm and s = 7 cm. PLEASE. How ?

GEOMETRY (SA oftriangular pyramid) - MathMate, Sunday, July 14, 2013 at 8:41am

Lateral surface area

=perimeter of base * apothem /2

=3b*s/2

(for a regular pyramid with a triangular base)

Area of triangular base with side b

=(√3)*b/2*(b/2)

=(√3)b²/4

GEOMETRY (SA oftriangular pyramid) - Anonymous, Sunday, July 14, 2013 at 10:05am

What is apothem ?

GEOMETRY (SA oftriangular pyramid) - Anonymous, Sunday, July 14, 2013 at 10:15am

why did you not include the height ?

- GEOMETRY (SA oftriangular pyramid) -
**MathMate**, Sunday, July 14, 2013 at 9:25pm
In the calculations of surface area of a pyramid, the height is not required if the apothem (slant height) is given.

The height is required, however, to calculate the volume of a pyramid.

In fact, the height h is not consistent, because h should always be less than the slant height, s.

If you could check the question for typos, there may be a different answer.

## Answer This Question

## Related Questions

- GEOMETRY (SA oftriangular pyramid) - Find the surface area of a triangular ...
- Mathematics - OPQRS is a right pyramid whose base is a square of sides 12cm each...
- geometry - The base of a pyramid is a square. The perimeter of the base is 20ft...
- geometry - A pyramid has a square base with each side measuring 105.5 meters. ...
- Math - VWXYZ is a rectangle-based pyramid where WX = 66 cm and XY = 32 cm. The ...
- Geometry - The base of a regular pyramid is a hexagon whose sides have length 5 ...
- Geometry - Use the figure of a square pyramid to answer the following questions...
- Maths - OPQRS is a right pyramid whose base is a square of sides 12cm each. ...
- Maths - OPQRS is a right pyramid whose base is a square of sides 12cm each. ...
- GEOMETRY - The present height of the pyramid of Khafre in Egypt is 137m.An ...

More Related Questions