GEOMETRIC TERMS

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GEOMETRIC TERMS
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Point is an exact location in space We say
Point A, Point B, Point C, etc. .B
.C .A
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Line a line goes on without end in both
directions. You can draw a line through any 2
points.
A B
This line can be written. . . . We say line AB or
line BA.
AB or BA
J
K
How would we say this line? How would we write it?
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Line segment is a part of a line that has two
endpoints. Its midpoint is halfway between the
endpoints.
X Y
We write this line segment as XY or YX. We say
line segment XY or line segment YX..
How would we say this ?How would we write it?
C D
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Parallel lines lines that are always stay the
same distance apart. They NEVER touch each
other. The symbol means is parallel to
We say line XY is parallel to line ST or XY ST
X Y
S T
A
C
B
What can we say about these 2 lines?
D
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Intersecting lines - lines that cross each other
(pass through the same point)
S
C
A
X
W
T
B
D
Line AB intersects line CD at point X.
What other lines intersect here? At what point
do they intersect?
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Perpendicular lines two lines that form right
angles are perpendicular to each other.
L
This symbol is used to show a right angle.
X
Y
M
Say line XY is perpendicular to line LM. The
symbol __ means is perpendicular to
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Ray Part of a line that starts at an endpoint
and goes on forever in one direction.
A B
Say ray AB We write it AB
K L
What is the name of this ray?
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ANGLE an angle is formed by two rays with a
common endpoint. The rays are the sides of the
angle. The common endpoint is the vertex of the
angle.
M
L
N
Rays LM and LN form the angle L. We can also name
the angle MLN or NLM. Point L is the vertex.
S
T
What rays make up this angle? What are the 3
names for this angle? What is the vertex of this
angle?
I
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Practice
E F

• Number your paper from 1-10 and answer the
  following
• Find 5 points.
• Find 4 pairs of intersecting lines.
• Find 3 line segments.
• Find 1 pair of parallel lines.
• Find 3 lines.
• Find 2 pairs of perpendicular lines.
• How many right angles?

J
A B C D
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G H
8. Name 4 rays. 9. Name 4 angles. 10. What are
the vertex points for each of the 4 angles you
named in 9?