Transformations and Reflections

​Transformations

October 31, 2022​

​Transformation: Changing a shape in the coordinate plane

​Shape before changing: Pre-image

Shape after changing: Image​

​

Example: ∠​A corresponds to ∠A'

∠​B corresponds to ∠B'

∠​C corresponds to ∠C'​

​Transformations of shapes can be:

​Rigid

​Non -Rigid

​Change shape size

​Doesn't Change Shape Size; Only Change Position

Multiple Choice

The transformation in this picture is

• Rigid

• Non-Rigid

• We Can't Tell!

Multiple Choice

Which of the following is a rigid transformation?

Multiple Choice

Is the following a rigid or a non-rigid transformation?

• Rigid

• Non-Rigid

• We Can't Tell!

Multiple Choice

Is the blue shape an Image or Pre-Image?

• Image

• Pre-Image

• We Can't Tell!

Multiple Choice

Which of the 4 types of transformations is non-rigid transformation?

• Rotation

• Reflection

• Translation

• Dilation

​Translations

​Sliding a shape in the coordinate plane by moving it

Right (+) or Left (-)

Up (+) or Down (-)

All points move the same distance!​

​Translation Rule

​T<x units, y units>

​

In this example, we can write this rule as:

T<x - 7, y - 9>​ of (ABCD)

Multiple Choice

Which rule describe the translation that maps PQRS into P'Q'R'S'?

• T<x + 8, y - 2>

• T<x + 8, y + 2>

• T<x - 8, y - 2>

• T<x - 8, y + 2>

Multiple Choice

What is the transformation rule for the following triangle.

• T<x-3, y + 4>

• T<x + 3, y + 4>

• T<x - 3, y - 4>

• T<x + 3, y - 4>

Draw

Translate point A

T<x - 5, y + 2>

​Reflections

Multiple Choice

Reflections over the x-axis change the _____.

• y-coordinate

• x-coordinate

• y-axis

• x-axis

Multiple Choice

Reflecting over the y-axis changes the _______.

• x-coordinate

• y-coordinate

• x-axis

• y-axis

Draw

Reflect the point over the y-axis

Draw

Reflect the point over the x-axis

Multiple Choice

What is the reflection of F (3, 4) over the x-axis?

• F' (-3, -4)

• F' (3, -4)

• F' (-3, 4)

• F' (4, 3)

Multiple Choice

Triangle JKL will be reflected over the y-axis. What will the coordinates of K' be?

• (-5, 2)

• (5, -2)

• (5, 2)

• (-5, -2)

Multiple Choice

What is the translation rule for triangle ABC?

• T<x + 4, y - 9>

• T<x + 4, y + 9>

• T<x - 4, y + 9>

• T<x - 4, y - 9>

​Complete the exit ticket.