Download Chapter 1 Vocabulary

 Chapter 1 Vocabulary 
Fill in the blanks using your textbook. Copy the examples from the board during class.
Term
Definition & Notation
* thought of as a
1
Point
2
Space
with no size
Notation:
set of all
* thought of as a series of
that extend
in two opposite directions without end
3
Line
Notation:
4
Collinear
points
points that lie on the same
5
Plane
* thought of as a flat
with no
thickness that extends without end
Notation:
6
7
Coplanar
Segment
figures in the same
part of a line consisting of
and all points between them
Notation:
endpoints
Example
8
Ray
part of a line consisting of
endpoint
and all points of the line on one side of the
endpoint
Notation:
9
Opposite rays
two
endpoint
rays with the same
Notation:
lines that do not intersect
10
Parallel lines
Symbols:
11
Skew lines
lines
(not parallel and do not intersect)
12
Parallel planes
planes that do not
13
Congruent
segments
segments with the same
Symbols:
the point on a line segment that divides it
14
Midpoint
into two
Notation:
segments
figure formed by two rays with the same
(called the vertex).
The sides are rays.
15
Angle
Notation:
an angle whose measure is between
16
Acute angle
17
Right angle
18
Obtuse angle
19
Straight angle
an angle whose measure is
20
Congruent
angles
angles with the same
an angle whose measure is
an angle whose measure is between
21
Perpendicular
two lines that intersect to form
angles
lines
Symbol:
22
Perpendicular
bisector
a line, segment, or ray that is perpendicular
to the segment at its
23
Angle bisector
a ray that divides an angle into two
coplanar angles
24
Vertical angles
two angles whose sides are
rays
25
Adjacent
angles
two
angles with a
common side, a common vertex, but no
common interior points
26
27
Complementary
angles
Supplementary
angles
two angles whose measures have a
of 90
two angles whose measures have a
of 180
28
Conjecture
conclusion reached using inductive
reasoning
29
Counterexample
an example for which the conjecture is
incorrect
30
Postulate
accepted statement of fact