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9-1B Surface Area of Pyramids. How are pyramids named? What is slant height? What is the lateral area of a pyramid? What is the lateral area formula for a pyramid? What is the surface area formula for a pyramid?. A pyramid is a polyhedron. Pyramids have only one base.
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9-1B Surface Area of Pyramids How are pyramids named? What is slant height? What is the lateral area of a pyramid? What is the lateral area formula for a pyramid? What is the surface area formula for a pyramid?
A pyramid is a polyhedron. Pyramids have only one base. The vertices of the base are connected to one point called the vertex of the pyramid. The height of the pyramid is the length of its altitude (goes through the center).
Pyramid Parts vertex lateral edge slant height altitude lateral face base
Netting a Pyramid • The lateral area is made up of what shape? What is the formula for the area of a triangle? What is the lateral area of your pyramid. • Find the area of the base of your pyramid. What is the shape of the base? 3. What is the surface area?
Theorem The lateral area of a regular pyramid is one-half the product of the perimeter of its base and the slant height of the pyramid. LA = ½ p s (slant) What is the shape of the base? Find it on the formula chart. What are you looking for? Lateral area.
Theorem The surface area of a regular pyramid is the sum of its lateral area and the area of its base. What is the shape of the base? Find the shape on the formula chart. Then find the SA formula.
Find the lateral area and surface area of the pyramid. What is the shape of the base? Square LA = ½ P slant LA = ½ (14)(4)(25) LA = 700 SA = 700 + 142 SA = 700 + 196 = 896 25 14
How are pyramids named? By the shape of their base. • What is slant height? The triangle height • What is the lateral area of a pyramid? The area of the triangular faces. • What is the lateral area formula for a pyramid? LA = ½ (perimeter)(slant height) • What is the surface area formula for a pyramid? SA = LA + area of the base.
Assignment 9-1B Page 612, 1-8, 10, 22, 23 NO FORMULAS WITH NUMBERS NO CREDIT