002 s.a. of prisms

OBJECTIVE

To find lateral area

and surface area

of a polyhedron,

the prism

Key Terms

Polyhedron

Altitude

Lateral Area

Net

Three-dimensional figures, or solids, can be made

up of flat or curved surfaces. Each flat surface is

called a face. An edge is the segment that is the

intersection of two faces. A vertex is the point that is

the intersection of three or more faces.

A cube is a prism with six square faces. Other

prisms and pyramids are named for the shape

of their bases.

PostulateWrite the formula for the

volume of a right

rectangular prism.

V = lwh We will assume prisms

are RIGHT from now on

VocabularyPolyhedron- A

geometric solid with

polygons as faces.

NEW DEFINITIONPrism-A polyhedron

with two polygonal

bases that are parallel

and congruent.

Right Prism - lateral edges

are perpendicular to the

planes of the bases.

VocabularyAltitude of a Prism - any

segment perpendicular

to the planes

containing the bases

with endpoints in these

planes. ( same as

HEIGHT)

VocabularyNet - a figure that can be

folded to enclose a

particular solid figure

ClassworkDraw a net for a right

triangular prism.

Draw a net for a right

pentagonal prism.

Classwork

Example 2A: Identifying a Three-

Dimensional Figure From a Net

Describe the three-dimensional figure that can be

made from the given net.

The net has six

congruent square

faces. So the net

forms a cube.

Example 2B: Identifying a Three-

Dimensional Figure From a Net



The net has one circular

face and one

semicircular face. These

are the base and sloping

face of a cone. So the net

forms a cone.

Check It Out! Example 2a



The net has four

congruent triangular

faces. So the net

forms a triangular

pyramid.

Check It Out! Example 2b



The net has two circular

faces and one

rectangular face. These

are the bases and curved

surface of a cylinder. So

the net forms a cylinder.

Lateral Area of a Prism -

sum of the areas of the

lateral faces.

Surface Area of a Prism -

sum of the lateral area

and the areas of the two

bases

Classwork

LATERAL AREA

SURFACE AREA

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.

Lateral Area of a Right Prism

Is their a short cut for

finding the lateral

area ?


The lateral area LA of a

right prism with height

h and perimeter of

base p is:

LA = Hp or L = Hp

Surface Area of a Right

PrismThe surface area SA of a

right prism with lateral LA

and the area of a base B

is:

SA = LA + 2B

or S =L + 2B

Volume

Volume equals Area of the

Base times the Height of the

object.

V = BHArea of the Base x Height of the object

Find the LA

Find the SA


Find the lateral area LA

of a right prism with

height 10cm, if the

base is a regular

hexagon with side

3cm.

Find the surface area

SA of a right prism

with height 10cm, if the

base is a regular

hexagon with side

3cm.(round answer to

nearest hundredth)

Example 1: Drawing Orthographic Views of

an Object

Draw all six orthographic views of the given object.

Assume there are no hidden cubes.

Example 1 Continued



Bottom

Example 1 Continued



Check It Out! Example 1



Check It Out! Example 1 Continued

Classwork/HomeworkPractice and Apply 7.2

P685 #’s 13-26 and 28-31

002 s.a. of prisms

Technology

Transcript of 002 s.a. of prisms