1. 3-D Shapes Topic 14: Lesson 3
3-D Shapes Topic 14: Lesson 3 Surface Area of Prisms Holt Geometry Texas ©2007

2. Objectives and Student Expectations
TEKS: G2B, G3B, G6B, G8D, G11D
The student will make conjectures about 3-D figures and determine the validity using a variety of approaches.
The student will construct and justify statements about geometric figures and their properties.
The student will use nets to represent and construct 3-D figures.
The student will find surface area and volume of prisms, cylinders, cones, pyramids, spheres, and composite figures.
The student will describe the effect on perimeter, area, and volume when one or more dimensions of a figure are changed.

3. Prisms and cylinders have 2 congruent parallel bases.
A lateral face is not a base. The edges of the base are called base edges. A lateral edge is not an edge of a base. The lateral faces of a right prism are all rectangles. An oblique prism has at least one nonrectangular lateral face.

4. An altitude of a prism or cylinder is a perpendicular segment joining the planes of the bases. The height of a three-dimensional figure is the length of an altitude.
Surface area is the total area of all faces and curved surfaces of a three-dimensional figure.
The lateral area of a prism is the sum of the areas of the lateral faces.

5. The net of a right prism can be drawn so that the lateral faces form a rectangle with the same height as the prism. The base of the rectangle is equal to the
perimeter of the base of the prism.

7. In your surface area and volume formula: P = Perimeter of the Base
The surface area formula is only true for right prisms. To find the surface area of an oblique prism, add the areas of the faces.
Caution!
In your surface area and volume formula:
P = Perimeter of the Base
B= Area of the Base
Remember!

8. Example: 1
Find the lateral area and surface area of the right rectangular prism. Round to the nearest tenth, if necessary.

9. Example: 2
Find the lateral area and surface area of the right triangular prism. Round to the nearest tenth, if necessary.

10. Example: 3
Find the surface area of the composite figure.

11. Example: 4
The edge length of the cube is tripled. Describe the effect on the surface area.

12. Example: 4 continued
24 cm
original dimensions: