GEO 11­26­12.notebook
November 26, 2012
Geometry
11/26/12
7.1, Rigid Motion in a Plane
Preimage: the original figure in a transformation
Image: the new figure in a transformation
Transformation: the operation that maps, or moves, the
preimage onto the image
3 Transformations:
Example 1, Naming Transformations
State the transformation
#1
#2
C
A'
B'
A
B
C
A
B
A'
C'
C'
B'
Both of the above transformations are
called...Isometries
An ISOMETRY is a transformation that preserves length,
angle measures, parallel lines, and distances.
Isometry vs. Not an Isometry
1.
2.
Nov 28­9:02 AM
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GEO 11­26­12.notebook
November 26, 2012
Name the transformation and state if it is an isometry or not.
1.
2.
3.
4.
Show that the transformation is an isometry by using the
distance formula to compare the lengths of the triangles.
A
A'
C
B
C'
B'
Find the value of each variable, given that the transformation
is an isometry.
6
96o
2ao
3d
92o
bo
7
c
Nov 28­9:54 AM
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