Warm UP 3-25-13
Translate (x – 9, y + 8)
1. B (-9, 12) B’ (-18, 20)
2. A (-12, -4) A’ (-21, 4)
3. T (22, -19) T’ (13, -11)
Warm up 3-26-13
Which one is even, odd, or neither?
1. f(x) = x
2. f(x) = 2x2 + 4
odd
even
3.
neither
Translations
Translate the image by
(x – 8, y + 2)
C  2,4   C'  10,6 
A  0, 8   A'  8, 6 
T  3,5   T '  11,7 
Translate the image by
(2x + 2, y – 3)
H 1,2 
 H'  4, 1
A  3, 5   A'  4, 8 
T  4, 1
 T ' 10, 4 
Find the pre-image
(x + 12, y – 17)
B  7, 12   B'  5, 29 
A  8, 2 
T  9,13 
 A'  20, 19 
 T '  21, 4 
Reflections
Reflect across the x-axis
 x,y    x, y 
Change the sign of the y-value
Reflect across the x-axis
C  2,4   C'  2, 4 
A  0, 8   A'  0,8 
T  3,5   T '  3, 5 
Reflect across the y-axis
 x,y     x,y 
Change the sign of the x-value
Reflect across the y-axis
H 1,2 
 H'  1,2 
A  3, 5   A'  3, 5 
T  4, 1
 T '  4, 1
Reflect across the line y = x
 x,y    y, x 
Swap x and y
Reflect
across
the line
Reflect
across
y = yx= x
B  7, 12   B'  12, 7 
A  8, 2 
T  9,13 
 A'  2,8 
 T ' 13,9 
Reflect
across
the line
Reflect
across
y = y-x= -x
 x,y    y,  x 
Swap and change both signs
Reflect
across
the line
Reflect
across
y = y-x= -x
W 13,21  W'  21, 13 
E  2,9 
 E'  9,2 
B 17, 24   B'  24, 17 
Lines of Symmetry
• How many lines of symmetry does the
polygon have?
3
Lines of Symmetry
• How many lines of symmetry does the
shape have?
2
Lines of Symmetry
• How many lines of symmetry does the
shape have?
5
Classwork
Reflections by
Mira
Worksheet
Warm up
1. A function is even. Point A(-3, 4) is on
the even function. Name another
point.
2. A function is even. Point B(9, 2) is on
the even function. Name another
point.
3. Reflect C(-5, -3) over the y-axis.
4. Reflect D(2, -4) over the x-axis.
5. Reflect E(-12, 4) over y = -x.
Review Homework
Skills Check
Are you ready?
Rotations
Rotate 90 Clockwise
about the Origin
(Same as 270 Counterclockwise)
 x,y    y,  x 
Change the sign of x and switch the order
Rotate 90° clockwise
about the origin
A(7, 3) 
 A'(
B(1, 4) 
 B'(
C(3, 1) 
 C'(
,
,
)
)
,
)
Rotate 90° clockwise
about the origin
A(7, 3)  A'  3,7 
B(1, 4)  B'  4, 1
C(3, 1)  C' 1, 3 
Rotate 90 Counterclockwise
about the Origin
(Same as 270 Clockwise)
 x,y     y, x 
Change the sign of y and switch the order
Rotate 90° counterclockwise
about the origin
E(3,  2) 
(
,
)
F(6, 5) 
(
,
)
G(0, 2) 
(
,
)
Rotate 90° counterclockwise
about the origin
E(3,  2)  E'  2, 3 
F(6, 5)  F'  5, 6 
G(0, 2)  G'  2,0 
Rotate 180 about the Origin
 x,y     x,  y 
ONLY Change the signs
Rotate 180° about the origin
Q(8,  2) 
 Q'(
,
)
R(8,  9) 
 R'(
,
)
S(2,  2) 
 S'(
,
)
T(2,  9) 
 T '(
,
)
Rotate 180° about the origin
Q(8,  2)  Q'  8,2 
R(8,  9)  R'  8,9 
S(2,  2)  S'  2,2 
T(2,  9)  T '  2,9 
Classwork
Rotations Practice
Worksheet
Homework
Rotations HW
Worksheet