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Lesson 4-5: Transformations & Symmetry

Scenario: Art & Design - Learn about transformations and symmetry through creative design projects!

Duration: 55-70 minutesScenario: Art & Design

Learning Objectives

  • Understand and perform geometric transformations
  • Identify and create symmetrical designs
  • Apply transformations to coordinate geometry
  • Use transformations in art and design projects

Art & Design Scenario

The Problem

You're creating a symmetrical pattern for a wallpaper design. You need to understand how to transform a basic shape to create a beautiful, balanced pattern using translations, rotations, and reflections.

Design Challenge:
Create a symmetrical pattern by transforming a triangle at (1, 1) using different transformations.

Pattern Design

Symmetrical pattern created using transformations

Types of Transformations

Four Basic Transformations

Translation (Slide)

Moving a shape without rotating or flipping it

Example: (x, y) → (x + 3, y + 2)

Rotation (Turn)

Turning a shape around a fixed point

Example: 90° clockwise around origin

Reflection (Flip)

Flipping a shape over a line

Example: Reflect over x-axis

Dilation (Scale)

Making a shape larger or smaller

Example: Scale factor of 2

Translation Example

Moving Shapes

A triangle has vertices at A(1, 1), B(3, 1), and C(2, 3). Translate it 4 units right and 2 units up.

Original vertices: A(1, 1), B(3, 1), C(2, 3)

Translation rule: (x, y) → (x + 4, y + 2)

New vertices: A'(5, 3), B'(7, 3), C'(6, 5)

Reflection Example

Flipping Over Lines

Reflect the point P(3, 4) over the x-axis and then over the y-axis.

Original point: P(3, 4)

Reflect over x-axis: P'(3, -4)

Reflect over y-axis: P''(-3, -4)

Symmetry

Types of Symmetry

Line Symmetry

A shape can be folded along a line and match exactly

Example: Letter "A" has vertical line symmetry

Rotational Symmetry

A shape looks the same after rotation

Example: Square has 4-fold rotational symmetry

Design Application

Create a symmetrical logo design using transformations. Start with a simple shape and use reflections and rotations to create a balanced, professional-looking logo.

Step 1: Start with a basic shape (triangle, square, circle)

Step 2: Apply reflections to create mirror images

Step 3: Use rotations to create rotational symmetry

Result: A balanced, symmetrical logo design

Practice Problems

Problem 1: Translation

Translate the point Q(2, 5) 3 units left and 4 units down.

Your solution:

Problem 2: Reflection

Reflect the point R(4, -2) over the x-axis.

Your solution:

Problem 3: Design Challenge

Create a symmetrical pattern by transforming a square at (0, 0) with side length 2. Use at least two different transformations.

Your design: