7 Math Vocabulary # 7 (3D Geometry).notebook
7th Grade Vocabulary
Ahrens
Three Dimensional (3D) Figures
An object with three different dimensions: length, width (or depth or breadth), and height. Also called a solid figure.
One­Dimensional
3D Geometry
Three­Dimensional
Two­Dimensional
length
height
width
length
length
width
3D Geometry Glossary
3D figures
Net
Surface Area
A 2­dimensional pattern which can be folded into a 3­
dimensional figure.
The total area of the surface of a 3­dimensional figure.
Surface Area=
2lw+2lh+2wh
+
+
+
8 u2
SA =
=
+
+
6 u2
2 12+2 6+2 8
12 u
SA=24+12+16
2
8 u2
=
6 u2
SA=52u2
12 u2
Net
Surface Area
Polyhedron
Polyhedron A three dimensional figure with all flat faces.
A 3­D figure whose
faces are all polygons.
Polyhedra
non­polyhedra
"Polyhedra" is the singular form of polyhedron
Polyhedron
Cubes
Cylinders
Prisms
Made of:
Pyramids
Faces
Cones
Edges
Vertices Polyhedron
1
7 Math Vocabulary # 7 (3D Geometry).notebook
Ahrens
Prism Prism
A 3­dimensional figure with two congruent, parallel bases, and all other faces are rectangles.
Prisms are named by the shape of their bases.
Pentagonal Prism
A polyhedron that has two congruent, polygon bases which are parallel to one another, sides that are rectangular, and named by the shape of their base. juice
box
Rectangular
Prism
Triangular Prism
Hexagonal
Prism
body
of
pencil
2 triangular bases
Block of
cheese
Triangular
Prism
3 rectangular faces
Prism
Prism
Pyramid
Pyramid A 3­dimensional figure with one base, a vertex at the top, and all other faces are triangles.
A polyhedron that has one polygon base with a vertex opposite of it,
sides that are triangular, and named by the shape of its base. Triangular Pyramid
1 base
All other faces are triangles
Pentagonal Pyramid
A vertex at the top
Pyramid
Pyramid
Euler's Formula
Vertex F + V ­ 2 = E
For any polyhedron that doesn't intersect itself, the number of edges is 2 less than the sum of the faces and vertices.
Faces: 6
Vertices: 8
Square
Pyramid
Point where two or more
straight lines/faces/edges meet. A Corner
6+8­2=12
A triangular pyramid has 4 vertices. Euler's formula
Vertex
Edges: 12
2
7 Math Vocabulary # 7 (3D Geometry).notebook
Ahrens
Edge Edge
The line segment where two faces meet.
Line segment formed where 2 faces meet.
edge
8 edges
A triangular pyramid has 6 edges. 10 edges
Edge
Edge
Face Face
A flat surface of a 3­d figure.
There is still debate over whether curved surfaces are faces.
Face
Flat surface of a polyhedron.
A triangular pyramid has 4 faces. (there is one you can't see) 6 faces
Face
Face
Cone
Cone A 3­dimensional figure with one circular base, a vertex at the top, and one curved surface connecting the two.
A polyhedron that has one circular base with a vertex opposite of it and sides that are curved. ice cream cone
curved
surface
1 Circular Base
1 Vertex 1 Curved Surface Cone
polyhedron
pencil tip
traffic cone
Cone
3
7 Math Vocabulary # 7 (3D Geometry).notebook
Ahrens
Cube
Cylinder
A 3­dimensional figure with 3 pairs of parallel, congruent, square bases.
12 Edges
8 vertices
A 3­dimensional figure with two­
congruent, circular bases, and one curved surface connecting them.
No vertices
2 congruent, parallel, circular bases
1 curved surface
6 faces
Cube
Cylinder
Cylinder Volume
The amount of space within a 3­dimensional object. Measured in cubic units.
A polyhedron that has two congruent circular bases which are parallel to one another and sides that are curved. 1
Pringles
curved
surface
candles
can
1
1
4
V=1 1 1
V= 1 cubic unit
3
v=lwh
v= 4 3 3
v= 36 u3
pizza
polyhedron
3
Cylinder
Volume
Volume The amount of
The number of cubic space occupied units needed to fill a 3D by a 3D figure.
figure (layering). volume of prisms
and cylinders: area of base x height Label: V = area of base x h V = 2m x 5m x 8m V = 80m3
Units3 or cubic units
Volume
4