1. What is dimension?

2. Undefined Terms in Geometry
Point A
Infinitely small
Location only
No length, area, or volume
Zero Dimensional
Labeled with a capital letter

3. Undefined Terms in Geometry
Line R1 A B x2 x1 x m A B
AB or BA
Straight
Infinite length, no area, no volume
One Dimensional
Labeled with two points or an italicized lower case letter

4. Undefined Terms in Geometry
Plane
(x,y) R2
Flat surface
Infinite area, no volume (thickness)
Two Dimensional
Labeled with a capital letter M x y

5. Space z x y R3
(x,y,z)
The set of all points.