BELLWORK # 3
Judging by appearances, will the lines intersect?
1.
2.
3.
Name the plane represented by each surface of the box.
4. The bottom
5. The front
6. The left side
7. The top
8. The back
9. The right side
UNIT 1.2 NOTES
Segments, Rays, and Parallel Lines
1.2 VOCABULARY
Copy the following vocabulary words on your paper.
Opposite rays
Parallel lines
Parallel planes
Ray
Segment
Skew lines
SEGMENT
Definition: The part of a line consisting
of two endpoints and all points between
them.
A
AB
Read “segment AB”
B
RAY
Definition: The part of a line consisting
of one endpoint and all the points of
the line on one side of the endpoint.
X
XY
Read “ray XY”
Y
OPPOSITE RAYS
Definition: Two collinear rays with the
same endpoint.
Q
R
RQ and RS are opposite rays.
Opposite rays always form a line.
S
Q
P
L
Name the segments and rays in the above figure.
The three segments are LP, PQ, and LQ.
The four rays are LP or LQ, PQ, PL, and QP or QL
PARALLEL LINES
Definition: Coplanar lines that do not
intersect.
AB
EF
SKEW LINES
Definition: Noncoplanar lines that do
not intersect.
These lines do not actually intersect – they are not on the same
plane. However, they are also, not parallel lines.
PARALLEL PLANES
Definition: Planes that do not intersect.
ABE
DCG
Plane ABCD
GH
A line and a plane that do not intersect are also parallel.