 P. 869 1-5 no calculators
 These problems are due in 3 min.

Date
Sec 1-1
Concept: Identify Points, Lines and Planes
Objectives:
Given basic concepts in Geometry, name and sketch geometric figures

 Point
 Line
 Plane

Point
Undefined.
It has no dimension. It is usually represented by a small dot
A
Label with Capital Letters

Line
Undefined
Extends in one dimension. Usually represented by a straight line with arrows on the ends.
l
A B
Labels: AB BA l

Plane: undefined Extends in two dimensions. Usually represented by a shape that looks like a table top.
A
B
M
C
Plane M or plane ABC

Key Terms – you probably already know some of these…
 Coplanar and Noncoplanar
 Collinear and Noncollinear
 Ray
 Segment
 Opposite ray
 Intersect

Collinear: points that lie on the same line
P I G S
Points P, I, G, and S are collinear

Non-Collinear:
Points that do not lie on the same line
O
G
D
Points D, O and G are noncollinear

Coplanar:
Points that lie in the same plane
G
M
A
S
H
T
Points M, A, T, H, S are coplanar

Non -Coplanar:
Points that do not lie in the same plane
G
M
A
S
H
T
Points G, S and H are non- coplanar

Line Segment: Part of a line that consists of 2 endpoints
A
AB or BA
B

Ray:
Part of a line that consists of a point called the initial point and all points on the line that extend in one direction.
B
A
A is the initial point
AB

Opposite Rays: If C is between A and B, then CA and CB are opposite rays
A
C
B

Intersect:
To have one or more points in common
Intersection:
The set of points that two or more geometric figures have in common

Example 1: L
P
C
N
M
O
1. Name 3 coplanar points
2. Name 3 collinear points
3. Name 3 non-collinear points
4. Name a line segment in two different ways
5. Name a ray

Example 1:
Cont.
C
P
L
N
M
O
6. Name a line in 2 ways
7. Name a point
8. Name the plane in two ways
9. What is the intersection of LO and plane C

Example 2: Sketch the figure described
A. A line and a plane that do not intersect

B. 2 planes that do not intersect and a line that intersects each plane in 1 point

Example 3: Determine if the point lies on the line
A. Y = x-4 A(5,1)
1 = 5-4
1=1
YES, it lies on the line
B. Y = 2x + 3 A(7, 16)
16 = 2(7) + 3
16 ≠ 17
NO, It doesn’t lie on the line

Example 4: Graph the inequality on the number line. Tell whether the graph is a segment, a ray or rays, a point or a line
X>2 or x<5
0 2 5
Line

Example 5: What kind of Geometric
Intersection does the photograph suggest?
The intersection of 2 lines
The intersection of a line and a plane

Today’s Work:
In Class:
Homework: