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How can you tell if an object is reflected?

Reflection 1. Pick up Homework from table. 2. Copy down the Essential Question (EQ). 3. Work on the Warm-up. Essential Question How can you tell if an object is reflected? Warm Up: Answer the question. Describe the transformation from blue to red.

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Identifying a Reflection

Is it a reflection? Explain Its is a reflection because, the red figure is flipped to make the blue figure Its is a not a reflection, because, the red figure is does not flipped to make the blue figure

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Tell whether the blue figure is a reflection. Explain

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Reflect over the __ –axis

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Reflect over the __ – axis?

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Fill in the points for A

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Fill in the points for A’

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What do you notice? What changed?

Pre Image → Image ( 1, 4 ) → ( 1, -4 ) ( 1, 1 ) → ( 1, -1 ) ( 4, 1 ) → ( 4, -1 ) The y sign changed. RULE: When reflection over The X- axis ( x, y ) → ( x, -y )

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Fill in the points for A

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Fill in the points for A’

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What do you notice? What changed?

Pre Image → Image ( 1, 2 ) → ( -1, 2 ) ( 4, 2 ) → ( -4, 2 ) ( 1, 5 ) → ( -1, 5 ) ( 4, 5 ) → ( -4, 5 ) The x sign changed. RULE: When reflection over The Y- axis ( x, y ) → ( -x, y )

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Reflection on Coordinate Grid Lesson 08-21-18

1. Copy down the Essential Question (EQ). 2. Work on the Warm-up. Essential Question How is reflecting over the x-axis different from reflecting over the y –axis ? Warm Up: Answer the question. Name and Describe the transformation from blue to red.

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Lets revisit yesterdays problem

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Lets revisit yesterdays problem

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Graph the image of the figure using the transformation given

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Graph the image of the figure using the transformation given

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Graph the image of the figure using the transformation given

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Graph the image of the figure using the transformation given

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Find the coordinates of the vertices of each figure after the given transformation.

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R‘ (3 , -5), N’ ( 4, 0), V’ ( 2, -1) , E(0, -4) K ‘ ( 1 , 1), N’ ( 4, 0), Q’ ( 4, 4)

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Write the rule to describe each transformation

Reflect over the y- axis

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How is rotation different from reflection?

1. Copy down the Essential Question (EQ). 2. Work on the Warm-up. Essential Question How is rotation different from reflection? Warm Up: Answer the question. Describe what happen in the 3 different pictures

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The meaning of a Words

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Center of rotation: the center point where the object turn.

Vocabulary Rotation: the turn transformation where an object rotates around a point. Center of rotation: the center point where the object turn. We will use ( 0, 0 ) as the center of rotation Angle of rotation: How much the object will turn

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Animation of Rotation Center of Rotation 4/24/2019

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Example 1: Identifying Rotations

Tell whether each transformation appears to be a rotation. Explain. A. B. No; the figure appears to be flipped. Yes; the figure appears to be turned around a point.

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Your Turn: Tell whether each transformation appears to be a rotation.

No, the figure appears to be a translation. Yes, the figure appears to be turned around a point.

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Degree of Rotation

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Degree of Rotation -90 90

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Rotation on Coordinate Grid 08-23-18

1. Copy down the Essential Question (EQ). 2. Work on the Warm-up. Essential Question How do you tell if an object is rotated by looking at its points. Warm Up: Answer the question. Describe any patterns in the picture

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90 clockwise rotation Formula (x, y) (y, x) English Formula:

Change the sign for the x, then switch the x and y. A(-2, 4) A’(4, 2) 4/24/2019

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Example: Rotate (-3, -2) 90 clockwise

Formula (x, y) (y, x) English Formula: Change the sign for the x, then switch the x and y. A’(-2, 3) (-3, -2) 4/24/2019

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90 counter-clockwise rotation

Formula (x, y) (y, x) English Formula: Change the sign for the y, then switch the x and y. A’(2, 4) A(4, -2) 4/24/2019

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Example: Rotate (-5, 3) 90 counter-clockwise

Formula (x, y) (y, x) English Formula: Change the sign for the y, then switch the x and y (-5, 3) (-3, -5) 4/24/2019

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180 rotation Formula (x, y) (x, y) English Formula:

Just change the sign for the x and y A’(4, 2) A(-4, -2) 4/24/2019

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Example: Rotate (3, -4) 180 Formula (x, y) (x, y)

English Formula: Just change the sign for the x and y (-3, 4) (3, -4) 4/24/2019

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90 CW (x, y) (y, x) 90 CCW (x, y) (y, x)

Rotation Formulas 90 CW (x, y) (y, x) 90 CCW (x, y) (y, x) 180 (x, y) (x, y) 4/24/2019

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Degree of Rotation -90 90

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Rotation on Coordinate Grid Part 2 08-24-18

1. Turn in your homework to the table. 2. Copy down the Essential Question (EQ). 3. Work on the Warm-up. Essential Question How is the rotation transformation similar to the reflection transformation? Warm Up: Answer the question. Does the shape get larger during a rotation?

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Draw the shape and rotate it 3 different ways:

(1) 90°clockwise, (2) 90°counterclockwise, and (3) 180°

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90°clockwise (2) 90°counterclockwise (3) 180°

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Draw the shape and rotate it 3 different ways:

(1) 90°clockwise, (2) 90°counterclockwise, and (3) 180°

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90°clockwise (2) 90°counterclockwise (3) 180°

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90°clockwise (2) 90°counterclockwise (3) 180°

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Formula (x, y) (y, x) English Formula: Change the sign for the y, then switch the x and y.

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Formula (x, y) (y, x) English Formula: Change the sign for the x, then switch the x and y.

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Formula (x, y) (x, y) English Formula: Just change the sign for the x and y

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