9.2 Surface Areas of Pyramids (Asynchronous)

9.2 Surface Areas of Pyramids (Asynchronous)

Pyramids

• The lateral faces of all pyramids are triangles.

• The height of each triangle (lateral face) is the slant height of the pyramid

• Looking at the the net of the pyramid we can see the square base with four lateral faces.

Pyramids Bases

• Most pyramids have a square base, but the base of a pyramid can be any polygon.

• A regular pyramid is classified as a pyramid whose base is a regular polygon.

• Remember, base is responsible for naming the pyramid as we can see with the examples on the right that all have different bases.

Multiple Choice

Please name this pyramid. (Remember to look at the base)

• Triangular Pyramid

• Square Pyramid

• Hexagonal Pyramid

Multiple Choice

Please name this pyramid. (Remember to look at the base)

• Triangular Pyramid

• Square Pyramid

• Hexagonal Pyramid

Height vs. Slant Height

• Height is the distance from the top of the pyramid straight down to the base.

• Height is perpendicular to the base.

• Slant Height is the height of the lateral face of a pyramid (or along the outside).

• Slant Height is perpendicular to the side of the base.