Nets andSurface Area

Lesson 11-2

Different Views

Perspective view of a cone

the side(or from any side view)

the top the bottom

Different angle views of a cone

Example: Different Views

* Note: The dark lines indicated a break in the surface.

Front Left Right Back Top

Sketch a rectangular solid 7 units long, 4 units wide, and 3 units high using Isometric dot paper .

Step 1: Draw the top of a solid 4 by 7 units.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sketches

Step 2: Draw segments 3 units down from each vertex (show hidden sides with dotted lines).

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sketches - continued

Step 3: Connect the lower vertices. Shade the top of the figure for depth if desired. You have created a corner view of the solid figure.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sketches - continued

Nets and Surface Area

Imagine cutting a cardboard box along its edges and laying it out flat. The resulting figure is called a net.

A net is very helpful in finding the surface area of a solid figure.

top

back

end

front

end

bottom

=

Find all that apply.

Let’s look at another net.This is a triangular pyramid.

Notice that all sides lay out to be triangles.

=

Find the surface area of the figure using a net.

1. First, imagine the figure represented as a net.2. Find the area of each face.3. Find the sum of all the individual areas.

610

6

336

33

10

66 6=

Surface area = (6 x 10) + (6 x 10) + (6 x 10) + ½(6)(33) + ½ (6)(33) = 60 + 60 + 60 + 93 + 93 = 180 + 183

Sketch the net and Find the surface area of the figure using a net.

Sketch the net and Find the surface area of the figure using a net.

Sketch the net and Find the surface area of the figure using a net.