Compositions of Similarity Transformations

Oct 13, 2025 by wbrum.org 138 views

Which Composition of Similarity Transformations Maps Polygon $A B C D$ to Polygon $A^{\prime} B^{\prime} C^{\prime} D^{\prime}$ ?

In geometry, similarity transformations are used to map one shape to another while preserving their similarity. These transformations can be composed to achieve more complex mappings. In this article, we will explore the composition of similarity transformations that maps polygon $A B C D$ to polygon $A^{\prime} B^{\prime} C^{\prime} D^{\prime}$ .

Similarity transformations are composed of two types of transformations: rigid motions and dilations. Rigid motions include translations, rotations, and reflections, while dilations involve scaling a shape by a certain factor.

Dilations

A dilation is a transformation that scales a shape by a certain factor. This factor is called the scale factor. If the scale factor is greater than 1, the shape is enlarged, and if it is less than 1, the shape is reduced.

Rotations

A rotation is a transformation that turns a shape around a fixed point called the center of rotation. The amount of rotation is measured in degrees.

Translations

A translation is a transformation that moves a shape from one position to another without changing its size or orientation.

Compositions of Similarity Transformations

To map polygon $A B C D$ to polygon $A^{\prime} B^{\prime} C^{\prime} D^{\prime}$ , we need to find the composition of similarity transformations that achieves this mapping.

Option A: A Dilation with a Scale Factor of $\frac{1}{4}$ and Then a Rotation

Let's consider option A, which involves a dilation with a scale factor of $\frac{1}{4}$ followed by a rotation.

Step 1: Dilation with a Scale Factor of $\frac{1}{4}$

The first step is to apply a dilation with a scale factor of $\frac{1}{4}$ . This means that each side of polygon $A B C D$ will be reduced by a factor of $\frac{1}{4}$ .

Step 2: Rotation

After the dilation, we need to apply a rotation to map the reduced polygon to the desired position. However, since the dilation reduces the size of the polygon, the rotation will not be able to map the polygon to the desired position.

Option B: A Dilation with a Scale Factor of $\frac{1}{2}$ and Then a Rotation

Let's consider option B, which involves a dilation with a scale factor of $\frac{1}{2}$ followed by a rotation.

Step 1: Dilation with a Scale Factor of $\frac{1}{2}$

The first step is to apply a dilation with a scale factor of $\frac{1}{2}$ . This means that each side of polygon $A B C D$ will be reduced by a factor of $\frac{1}{2}$ .

Step 2: Rotation

After the dilation, we need to apply a rotation to map the reduced polygon to the desired position. Since the dilation reduces the size of the polygon, the rotation will be able to map the polygon to the desired position.

In conclusion, the composition of similarity transformations that maps polygon $A B C D$ to polygon $A^{\prime} B^{\prime} C^{\prime} D^{\prime}$ is a dilation with a scale factor of $\frac{1}{2}$ followed by a rotation.

The final answer is option B: A dilation with a scale factor of $\frac{1}{2}$ and then a rotation.

[1] Geometry: A Comprehensive Course, by Dan Pedoe
[2] Similarity Transformations, by Math Open Reference

In our previous article, we explored the composition of similarity transformations that maps polygon $A B C D$ to polygon $A^{\prime} B^{\prime} C^{\prime} D^{\prime}$ . In this article, we will answer some frequently asked questions about similarity transformations.

Q: What is a similarity transformation?

A similarity transformation is a transformation that maps one shape to another while preserving their similarity. This means that the transformation preserves the ratio of the lengths of corresponding sides of the shapes.

Q: What are the types of similarity transformations?

There are two types of similarity transformations: rigid motions and dilations. Rigid motions include translations, rotations, and reflections, while dilations involve scaling a shape by a certain factor.

Q: What is a dilation?

Q: What is a rotation?

A rotation is a transformation that turns a shape around a fixed point called the center of rotation. The amount of rotation is measured in degrees.

Q: What is a translation?

A translation is a transformation that moves a shape from one position to another without changing its size or orientation.

Q: Can a similarity transformation be composed of multiple transformations?

Yes, a similarity transformation can be composed of multiple transformations. For example, a dilation followed by a rotation is a composition of two similarity transformations.

Q: How do I determine the order of transformations in a composition?

To determine the order of transformations in a composition, you need to consider the effect of each transformation on the shape. For example, if you want to map a polygon to a new position, you may need to apply a dilation first to reduce the size of the polygon, and then apply a rotation to map the reduced polygon to the desired position.

Q: Can a similarity transformation be reversed?

Yes, a similarity transformation can be reversed. For example, if you apply a dilation with a scale factor of 2, you can reverse the transformation by applying a dilation with a scale factor of $\frac{1}{2}$ .

Q: What are some real-world applications of similarity transformations?

Similarity transformations have many real-world applications, including:

Computer graphics: Similarity transformations are used to create 3D models and animations.
Engineering: Similarity transformations are used to design and analyze mechanical systems.
Architecture: Similarity transformations are used to design and analyze buildings and other structures.

In conclusion, similarity transformations are an important concept in geometry and have many real-world applications. By understanding the types of similarity transformations and how to compose them, you can solve a wide range of problems in mathematics and engineering.

The final answer is that similarity transformations are a powerful tool for mapping shapes and have many real-world applications.

[1] Geometry: A Comprehensive Course, by Dan Pedoe
[2] Similarity Transformations, by Math Open Reference

This article is for educational purposes only and is not intended to be a comprehensive treatment of the subject.