1. This means 4 to the right and 2 up . . .
Name:________________________________________________________________________________Date:_____/_____/__________
BRAIN BLITZ/Warm-UP
Plot the following points. Label each point with its appropriate letter! 1)
A (2,6)
B (3, -3)
C (-4,0)
D (0, -4)
E (-2,-5)
F (-4,7)
Translation Review:
TRANSLATE (slide) point A according to the following directions, and identify where A prime would be. Then plot A prime on the coordinate plane.
2) Translate (4, 2):
A(-3,5); AI ________
3) Translate (-2, -7):
4) Translate (8, -3):
This means 4 to the right and 2 up . . . A

2. Remember, x and y switch with each turn!
ROTATIONS
Fill-in-the-Blanks:
A rotation is a ____________________ .
3) The stations of rotation are 90°, 180°, __________, and 360°
Track the movement of point A by filling in the following tables:
4) )
Clockwise:
Orig.
(4 , 3) Q1
90°
( , )
180°
270°
360°
Counter-Clockwise:
Orig.
(4 , 3) Q1
90°
( , )
180°
270°
360° A
Remember, x and y switch with each turn!
Rotate Point A according to the following directions, and identify where A prime would be:
90° clockwise:
A(-3,5); AI ________
7) 180° counter-clockwise:
8) 270° clockwise:
9) 270° counter-clockwise: A

3. transformations (reflections). . .
Today’s Lesson:
Part 1
What:
transformations (reflections). . .
Why:
To perform reflections of figures on the coordinate plane.

4. A reflection is a ____________ .
What is a Reflection??
A reflection is a ____________ .
We will reflect on the coordinate plane over both the x axis and the ___________________________ . A AI
flip
y axis

5. (Repeat above process for all points on figure)
How do we perform a reflection??
Identify the line of reflection, or the line that the figure will ____________ over.
Choose a point on the original figure (pre-image), and count the number of grid lines that lie between the point and the line of __________________ .
Then, count out the ___________ number of grid lines on the OTHER side of the line of reflection. This is where the new point will be (the “prime” point).
(Repeat above process for all points on figure)
flip
reflection
SAME
Example

6. Reflect the figure over the “x” axis:
Perform the following reflections:
Reflect the figure over the “x” axis:
Matching points MUST be the same distance from the line of reflection! A B C D CI DI BI AI
Point A: (-3, 6)
Point AI : _______
(-3,-6)
Hmmm, what is interesting about above points?

7. Hmmm, notice that only the “x” value changed!
Reflect the figure over the “y” axis:
How can you tell that the below transformation is a reflection and NOT a translation?? AI BI A B C D DI CI
Point A: (7, 5)
Point AI : _______
(-7, 5)
Hmmm, notice that only the “x” value changed!

8. Reflect the figure over the “x” axis:BI AI CI A B C
Point A: (-1, -8)
Point AI : _______
(-1, 8)
This time, only the “y” value changed! Why??
Hint: “Right or left changes x! Up or down changes y!”

9. Reflect the figure over the “y” axis:B C CI AI BI
Point A: (-1, -7)
Point AI : _______
(1, -7)
By now, we can see that a RIGHT/LEFT flip changes X to its opposite; while an UP/DOWN flip changes ____ to its opposite!! This always works! y

10. transformations (dilations). . .
Today’s Lesson:
Part 2
What:
transformations (dilations). . .
Why:
To perform dilations of figures on the coordinate plane.

11. Remember, a dilation is any ____________________________.
What is it??
Remember, a dilation is any ____________________________.
The scale factor controls how large or ________________ the figure will become. We dilate according to the ______________________ .
More specifically, we ________________ EVERY coordinate by the scale factor.
re-sizing
small
scale factor
multiply

12. Original Coordinates: Multiply everything by 2!!
To be completed together in class: AI BI A B CI C
ENLARGEMENT!
Directions: Plot the original points as indicated. Connect the points to make a right triangle. Then, perform the given dilation.
Original Coordinates:
A (-2, 4)
B (2, 4)
C (2, 1)
Dilate by
Scale Factor of 2 AI
( , ) BI
( , ) CI
-4 8
4 8
4 2
Multiply everything by 2!!

13. Original Coordinates: Multiplying by ½ is the SAME as dividing by 2!!AI BI C CI
REDUCTION!
Directions: Plot the original points as indicated. Connect the points to make a right triangle. Then, perform the given dilation.
Original Coordinates:
A (-4, 6)
B (2, 6)
C (2, 3)
Dilate by
Scale Factor of ½ AI
( , ) BI
( , ) CI
( , )
-2 3
1 3
Multiplying by ½ is the SAME as dividing by 2!!

14. Soooo, when a figure is dilated by a scale factor GREATER than one, the image gets ________________________.
However, when a figure is dilated by a scale factor LESS than one (fraction), the image gets __________________________________ .
BIGGER
smaller

15. homework
Finish homework packet (handed out in class). See last 4 slides of this powerpoint for an extra copy.

16. END OF LESSON
The next slides are student copies of the notes and necessary handouts for this lesson. These were handed out in class and filled-in as the lesson progressed.

17. (Repeat above process for all points on figure)
Math-7 NOTES
DATE: ______/_______/_______
What: transformations (reflections). . .
Why: To perform reflections of figures on the coordinate plane.
NAME:
What is a Reflection??
A reflection is a ____________ .
We will reflect on the coordinate plane over both the x axis and the ___________________________ . A AI
How do we perform a reflection??
Identify the line of reflection, or the line that the figure will ____________ over.
Choose a point on the original figure (pre-image), and count the number of grid lines that lie between the point and the line of _________________ .
Then, count out the ___________ number of grid lines on the OTHER side of the line of reflection. This is where the new point will be (the “prime” point).
(Repeat above process for all points on figure)

18. Perform the following reflections:
Point A: (-1, -7)
Point AI : _______

19. Part 2 To be completed together in class:
What: transformations (dilations). . .
Why: To perform dilations of figures on the coordinate plane.
Remember, a dilation is any _______________________.
The scale factor controls how large or __________the figure will become. We dilate according to the ____________________________ .
More specifically, we _________________ EVERY coordinate by the scale factor.
To be completed together in class:
Directions: Plot the original points as indicated. Connect the points to make a right triangle. Then, perform the given dilation.
Original Coordinates:
A (-2, 4)
B (2, 4)
C (2, 1)
Dilate by Scale Factor of 2
AI ( , )
BI ( , )
CI ( , )
Multiply everything by 2!

20. Original Coordinates: A (-4, 6) B (2, 6) C (2, 3)
Directions: Plot the original points as indicated. Connect the points to make a right triangle. Then, perform the given dilation.
Original Coordinates:
A (-4, 6)
B (2, 6)
C (2, 3)
Dilate by Scale Factor of ½
AI ( , )
BI ( , )
CI ( , )
Multiplying by ½ is the SAME as dividing by 2!!
Soooo, when a figure is dilated by a scale factor GREATER than one, the image gets _________________________________.
However, when a figure is dilated by a scale factor LESS than one (fraction), the image gets __________________________________ .

21. Reflections classwork
Name:__________________________________________________________Date:_____/_____/__________
Reflections classwork

23. Dilations classwork Date:_____/_____/__________
Name:___________________________________ D C A B

25. Math-7 HOMEWORK “Reflections” 1) Reflection across the x axis:
NAME: ________________________________________________________________________________DATE:_____/_____/__________
1) Reflection across the x axis:
2) Reflection across the y axis:
3) Reflection across the y axis:
4) Reflection across the x axis:
5) Reflection across the x axis:
6) Reflection across the y axis:

26. Remember: “RIGHT or LEFT changes X, UP or DOWN changes Y!!
7) Reflection across the x-axis:
8) Reflection across the y-axis:
Hint: Flipping over x is an UP or DOWN flip!
Hint: Flipping over y is a RIGHT or LEFT flip!
9) Write a rule to describe the below reflection:
Hint: Look for the prime marks!!

27. Math-7 HOMEWORK “Dilations”
NAME: ________________________________________________________________________________DATE:_____/_____/__________
Use your NOTES to help you fill blanks in!!
(2, 4)
(1, 1)
(4, 0)
Hint: MULTIPLY all original coordinates by the scale factor!!

28. You may use a calculator to assist you in multiplying by this scale factor.
Hint: Multiplying by 1/3 is the SAME as dividing by so divide for this one!
Hint: Write down the original coordinates of one of the points (doesn’t matter which one). Then, write the new coordinates for that SAME point. How did it change??