101

1
10-1 10-2 Space Figures, Nets Diagrams

• Objective To recognize nets to make
  isometric drawings of space figures.

2
Polyhedron A 3-dimensional figure whose
surfaces are polygons.
Faces the polygons making up the sides.
Edges A segment that is formed by the
intersection of two faces.
Vertex A point where the three or more edges
intersect.
of Faces
of Edges
of Vertices
3
Space Figures and Nets
Net A two-dimensional pattern that you can fold
to form a three-dimensional figure.
F
F
D
A
B
C
D
A
Cube A polyhedron with six faces, each of which
is a square.
E
4
1 Identifying a Net

• Is this pattern a net for a cube? If so, name
  the letters that will appear on opposite faces.

Cube?
A
Yes
Opposite faces
B
D
E
F
A and C
B and E
C
D and F
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2 Drawing a Net

• Draw a net for the graham cracker box. Label the
  net with its dimensions.

14
Graham Crackers
20
20
20
20
14
7
7
7
7
14
Graham Crackers
20
14
6
Eulers Formula

• The number of faces (F), vertices (V), and edges
  (E) of a polyhedron are related by the formula

7
3 Using Eulers Formula

• Use Eulers Formula to find the number of edges
  of a polyhedron with 6 faces and 8 vertices

8
Cross-Sections

• Cross Section The intersection of a solid and a
  plane.