1. 1-7 transformations on the coordinate plane
Chapter 1
1-7 transformations on the coordinate plane

2. Objectives Students will be able to:
Identify reflections, rotations, and translations.
Graph transformations in the coordinate plane.

3. What is a transformation?
A transformation is a change in the position, size, or shape of a figure.
The original figure is called the preimage. The resulting figure is called the image.
A transformation maps the preimage to the image. Arrow notation () is used to describe a transformation, and primes (’) are used to label the image.

4. Types of transformations

5. Reflections Types of reflections: Reflection across the y-axis
Reflection across the x-axis
Reflection across a specific line

6. Example #1
Work on reflection worksheet problems 1-3

7. Rotation Definition of Rotation
A Rotation is a transformation that turns a figure about a fixed point.
More about Rotation
Rotation is also called as turn.
The fixed point around which a figure is rotated is called as centre of rotation.

8. Example#2
Lets work on problems 1-3 on rotation worksheet

9. Translation Every point of the shape must move: the same distance
Moving a shape, without rotating or flipping it. "Sliding".
The shape still looks exactly the same, just in a different place.
To Translate a shape:
Every point of the shape must move:
the same distance
in the same direction.

10. Example#3
Do worksheet translation problem 1-3

11. Identifying transformations
Identify the transformation. Then use arrow notation to describe the transformation.
90° rotation, ∆ABC  ∆A’B’C’

12. Example#4
Identify the transformation. Then use arrow notation to describe the transformation.
reflection, DEFG  D’E’F’G’

13. Drawing Transformation
A figure has vertices at A(1, –1), B(2, 3), and C(4, –2). After a transformation, the image of the figure has vertices at A'(– 1, –1), B'(–2, 3), and C'(–4, –2). Draw the preimage and image. Then identify the transformation.
The transformation is a reflection across the y-axis because each point and its image are the same distance from the y-axis.

14. Example#5
A figure has vertices at E(2, 0), F(2, -1), G(5, -1), and H(5, 0). After a transformation, the image of the figure has vertices at E’(0, 2), F’(1, 2), G’(1, 5), and H’(0, 5). Draw the preimage and image. Then identify the transformation.
The transformation is a 90° counterclockwise rotation.

15. Homework
Lets work on all transformation worksheet problems 1-8

16. Closure
Today we learn about transformations and how they work on the coordinate plane.
Next class we are going to continue with chapter 2

17. Have a great day