Transcript Undefined Terms and Definitions

Undefined Terms and
Definitions
Undefined Terms
Point
• simply a location
• represented by a dot
• named with a capital letter
• no shape
• no size
Undefined Terms (cont.)
Line
• made up of points
• no thickness or width
• drawn with an arrowhead at each end
• named by the letters representing two points on
the line or by a lowercase script letter
• has symbol in label above two letters
SL or LS
Undefined Terms (cont.)
Plane
• flat surface made up of points
• no depth
• extends infinitely in all directions
• drawn as a shaded, slanted four-sided figure
• named by a capital script letter or by the
letters naming three points in the plane that
are not on the same line
Definitions (cont.)
Collinear - points on the same line
Coplanar - points that lie on the same plane
Intersection – The point(s) in common among
figures
Space – A boundless three-dimensional set of all
points.Space can contain lines and planes.
Locus – A set of points that all satisfy a particular
condition.
Use the figure to name each of the following.
a. a line containing point X
Answer: line c,
b. a plane containing point Z
Answer: plane P, plane XYZ, plane ZYX, plane YZX,
plane XZY, plane ZXY, plane YXZ
VISUALIZATION Name the geometric shape
modeled by each object.
a. a colored dot on a map used to mark the location of a city
Answer: point
b. the ceiling of your classroom
Answer: plane
a. How many planes appear in this figure?
Answer: two
b. Name three points that are collinear.
Sample answer: A, X, and Z
c. Are points X, O, and R coplanar? Explain.
Answer: Points X, O, and R all lie in
plane T, so they are coplanar.
d. At what point do
Answer: R
and
intersect?