Transcript Sec 1-1 Points, Lines and Planes

Warm-ups

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
3-Undefined Terms in Geometry
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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
M
B
C
Plane M or plane ABC
Key Terms – you probably already
know some of these…

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Coplanar and Noncoplanar
Collinear and Noncollinear
Ray
Segment
Opposite ray
Intersect
Collinear:
P
points that lie on the same line
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
A
M
S
H
T
Points G, S and H are non- coplanar
Line Segment:
A
AB or BA
Part of a line that consists of 2
endpoints
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:
A
If C is between A and B, then CA
and CB are opposite rays
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
L
Example 1:
C
N
P
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
L
Example 1:
Cont.
C
N
P
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)
B. Y = 2x + 3 A(7, 16)
16 = 2(7) + 3
1 = 5-4
1=1
YES, it lies on the
line
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
Line
5
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: