GEO 11­30­11.notebook
November 30, 2011
Geometry
11/30/11
Please take out the following assignments:
7.1, page 399, #1-41(odd)
7.2, page 407, #1-29(all) 48,49
Please do the following problems:
The following are the coordinates for a quadrilateral:
A (­4, 0), B (­4, 2), C (­2, 2), D (­2,0)
a) Reflect the shape over the y­axis.
b) Reflect ABCD over y = ­3.
c) REVIEW: What is the length of AC?
7.3, Rotations
Rotation: a transformation in which a figure is turned about a fixed point.
P
P
Theorem 7.2, Rotation
A rotation is an isometry.
State the segment or triangle that represents the image.
C
a) 90 clockwise rotation of AB about P
b) 180 clockwise rotation of KF about P
J
B
A
D
P
K
L
F
M
H
c) 180 rotation of triangle KEF about P
d) 270 clockwise rotation of triangle BCJ about P
E
G
Name the coordinates of the vertices of the image after a
clockwise rotation of the given number of degrees about the
origin.
a) 90o
B
C
A
D
b) 1800
Nov 29­3:50 PM
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GEO 11­30­11.notebook
November 30, 2011
Rotational Symmetry: a figure has rotational symmetry if it can be mapped onto itself by a rotation of 180o or less.
Does the figure have rotational symmetry?
#1
#2
YES!
YES!
#3, Do the initials SHS have rotational symmetry? YES!
Nov 30­10:18 AM
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GEO 11­30­11.notebook
November 30, 2011
Nov 30­12:23 PM
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