1. Warm Up
Problem of the Day
Lesson Presentation
Lesson Quizzes

2. Warm Up
Identify each transformation from the original to the image, and tell whether the two figures are similar or congruent.
1. Original: A(-2, -1), B(-2, 1), C(1, 1), D(1, -1)
Image : A'(-4, -2), B'(-4, 2), C '(2, 2), D'(2, -2)
Dilation; similar
2. Original: A(1, 1), B(1, 4), C(5, 1)
Image : A'(1, -1), B'(1, -4),C '(5, -1)
Reflection; congruent

3. Problem of the Day
A football field is in the shape of a rectangle with a length of 360 feet and a width of 160 feet. If a coach is drawing a football field on a chalkboard and has made a 54-cm line for the length, how
long should the line for the width of the field be?
24 cm

4. Learn to identify the image of a figure after a combined transformation is performed, and
determine whether the final image is similar or congruent to the original.

5. Many famous geometric designs are created by combining transformations of various geometric figures.
The mysterious crop circles shown here appear to be composed of combined rotations and dilations. If you consider the one piece that is rotated to create the design, you can see that it is similar to each of its
rotations.

6. Additional Example 1: Transformation Sequences and Congruence
Identify the combined transformations from the original to the final image, and tell whether the two figures are similar or congruent.
Original : A(1, 1), B(2, –1), C(3, –5), D(2, –5)
First Image: A'(1, 1), B'(2, 1), C'(3, 5), D'(2, 5)
Final Image: A"(–3, –2), B"(–2, –2), C"(–1, 2), D"(–2, 2)
The original image to the first image: Reflection across x-axis
The first image to the final image: Translation 4 units left and 3 units down
The two figures are congruent.

7. The original image to the first image: Reflection across x-axis
Check It Out: Example 1
Identify the combined transformations from the original to the final image, and tell whether the two figures are similar or congruent.
Original: A(2, –1), B(4, –1), C(5, –5), D(3, –5)
First Image: A'(2, 1), B'(4, 1), C'(5, 5), D'(3, 5)
Final Image: A"(–5, –5), B"(–3, –5), C"(–2, –1), D"(–4, –1)
The original image to the first image: Reflection across x-axis
The first image to the final image: Translation 7 units left and 6 units down
The two figures are congruent.

8. Additional Example 2: Transformation Sequences and Similarity
Identify the combined transformations from the original to the final image, and tell whether the two figures are similar or congruent.
Original : A(1, 0), B(3, 1), C(4, –1), D(2, –2)
First Image: A'(–1, 0), B'(–3, –1), C'(–4, 1), D'(–2, 2)
Final Image: A"(–0.5, 0), B"(–1.5, –0.5),C"(–2, 0.5),D"(–1, 1)
The original image to the first image: Rotation of 180 around origin
The first image to the final image: dilation with scale factor of 0.5
The two figures are similar.

9. Check It Out: Example 2
Identify the combined transformations from the original to the final image, and tell whether the two figures are similar or congruent.
The original image to the first image: Translation3 units left and 2 units down
The first image to the final image: dilation with scale factor of 2
The two figures are similar.

10. Additional Example 3: Finding Sequences of Transformations
Find a sequence of at least two combined transformations from the original to the final image. Justify your answer.
Original : A(–5, 1), B(–2, 4), C(–1, 1)
Final Image: A"(1, –5), B"(4, –2), C"(1, –1)
Reflection across the x-axis; rotation of 90 counter-clockwise around the origin.

11. Reflection across the x-axis; translation 1 unit up
Check It Out: Example 3
Find a sequence of at least two combined transformations from the original to the final image. Justify your answer.
Original : A(–5, 1), B(–2, 4), C(–1, 1)
Final Image: A"(–5, –1), B"(–2, –4), C"(–1, –1)
Reflection across the x-axis; translation 1 unit up

12. Lesson Quiz for Student Response Systems
Lesson Quizzes
Standard Lesson Quiz
Lesson Quiz for Student Response Systems 12 12

13. Lesson Quiz : Part-I
Identify the combined transformations from the original to the final image, and tell whether the two figures are similar or congruent.
1. Original Δ ABC: A(1, 2), B(3, 4),
C(3, 2)
First image : Δ A'B'C': A' (2, 21),
B'(4, 23), C '(2, 23)
Final image Δ A"B"C " :
A"(21, 3), B"(1, 1), C "(21, 1)
A 90° clockwise rotation around the origin followed by a translation of 3 units left and 4 units up; congruent

14. Lesson Quiz : Part-II
2. Original ABCD: A(22, 1), B(1, 1),
C(0, 2), D(22, 2)
First image A'B'C 'D': A'(22, 21),
B'(1, 21), C '(0, –2), D'(22, 22)
Final image A"B"C "D": A"(24, 22),
B"(2, 22), C "(0, 24), D"(24, 24)
A reflection across the x-axis followed by a dilation with a scale factor of 2 with the origin as the center of dilation; similar

15. Lesson Quiz : Part-III
Find a sequence of at least two combined transformations from the original to the final image.
180° rotation around the origin followed by a translation of 1 unit
right and 1 unit down.

16. Lesson Quiz for Student Response System
1. Triangle ABC has the following coordinates:
A(–5, 1), B(–2, 4), C(–1, 1). Which triangle coordinates represent a reflection across the y-axis?
A. A’(–5, 1), B’(–2, 4), C’(–1, 1)
B. A’(5, 1), B’(2, 4), C’(1, 1)
C. A’(–5, –1), B’(–2, –4), C’(–1, –1)
D. A’(1, –5), B’(4, –2), C’(1, –1)

17. Lesson Quiz for Student Response System
2. Triangle ABC has the following coordinates: A(–5, 1), B(–2, 4), C(–1, 1). Which triangle coordinates represent a 90 clockwise rotation around the origin?
A. A’(–5, 1), B’(–2, 4), C’(–1, 1)
B. A’(5, 1), B’(2, 4), C’(1, 1)
C. A’(–5, –1), B’(–2, –4), C’(–1, –1)
D. A’(1, 5), B’(4, 2), C’(1, 1)