Corbett Maths
Enlargements with Fractional Scale Factors
Enlargements make it bigger, right? A video shows viewers how to perform a basic dilation with a fractional scale factor. They learn how to use the scale factor to find the location of the transformed vertex by multiplying the horizontal...
Mathed Up!
Negative Scale Factor
Class members investigate the effect of a negative scale factor dilation on coordinate shapes as they watch a short video that shows an example of a geometric figure undergoing a dilation with a negative scale factor. Learners then try a...
Corbett Maths
Enlargements with Negative Scale Factor
How will a scale factor affect a figure—negatively? Using a grid, the narrator of an engaging video performs a dilation with a negative scale factor. The presenter compares a positive scale factor with a negative scale factor to explain...
EngageNY
Scale Factors
Is it bigger, or is it smaller—or maybe it's the same size? Individuals learn to describe enlargements and reductions and quantify the result. Lesson five in the series connects the creation of a dilated image to the result. Pupils...
Corbett Maths
Describing Enlargements
What caused that to happen? Using three aspects, a video demonstrates how to describe an enlargement or dilation. The presenter counts the lengths of the sides to determine the scale factor and a ruler to find the center of dilation.
Mathed Up!
Enlargements
Make enlargements with and without centers. Pupils work through seven problems dealing with dilations or enlargements. The first couple items are strict enlargements without centers, while the others have centers. Class members also...
Corbett Maths
Enlargements
Count on the scale to enlarge a figure. The video shows how to create an enlargement given a scale factor and a center of enlargement. The presenter multiplies the vertical and horizontal distance by the scale factor to find the new...
Corbett Maths
Enlargements Using Ray Method
Figure out what to do when there is no grid to count. Using a ruler and a sharp pencil, the narrator shows how to perform a dilation when the figure is not on a grid. The ray method works by drawing a ray from the center of dilation...
EngageNY
Scale Drawings
Are you searching for a purpose for geometric constructions? Use an engaging approach to explore dilations. Scholars create dilations using a construction method of their choice. As they build their constructed dilation, they strengthen...
Corbett Maths
Finding the Centre of Enlargement
Where did the transformation begin? Using a ruler, the narrator of a short presentation shows how to find the center of enlargement for transformed figures. Worksheets provide the class members an opportunity to practice the newly...
EngageNY
Making Scale Drawings Using the Ratio Method
Is that drawn to scale? Capture the artistry of geometry using the ratio method to create dilations. Mathematicians use a center and ratio to create a scaled drawing. They then use a ruler and protractor to verify measurements.
Curated OER
Investigating Scale Factors with the Geometer's Sketchpad
Students use Geometer's Sketchpad to examine the scale factor when in is applied to the length of a figure's sides. They look at how the scale factor affects the side lengths, perimeter, and area of the figure that result. They work with...
Curated OER
Geometry Worksheet 9.5: Rotational Symmetry
In this rotational symmetry worksheet, high schoolers solve 14 short answer and graphing problems. Students identify the order and magnitude of given figures. High schoolers find the scale factor of a dilation given a graph.
Curated OER
Enlargement Worksheet
In this geometry worksheet, students figure out the center of enlargement and the scale being used. They find the image and pre-image and label it. There are 7 questions.
Curated OER
How Big is Barbie?
Students measure various dimensions of a male and a female dolls body and scale them proportionally to average human measurements. They calculate the appropriate scale factor (magnitude) to enlarge their doll and apply that scale factor...
Curated OER
Six Exercise Sets on Transformations
Middle and high schoolers solve fifteen problems from six exercise sets covering transformations, reflections, rotations, and enlargements. The solutions are provided.
Curated OER
Similarity
In this similarity worksheet, students identify similar shapes. They determine the scale factor of the similar shapes and find their volume and area. Students enlarge shapes according to the given scale factor. They determine the...
Inside Mathematics
Hopewell Geometry
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
Mathed Up!
Mixed Transformations
Viewers learn how to identify and perform a variety of transformations with a video that provides seven items on transformations. Pupils demonstrate their understanding of dilations, reflections, rotations, and translations. The video...
Curated OER
Unit 14 - Loci and Transformations
In this transformations activity, students solve 25 short answer problems. Students dilate, reflect, and translate points and figures in the coordinate plane. Students determine scale factors and lines of symmetry of figures.
Curated OER
Corresponding Parts of Similar Triangles
Here is a lesson that has learners take a look at corresponding parts of similar triangles, ratios of similarity, reductions and enlargements. They'll manipulate the scale factor (r) to observe the changes in similar triangles and then...
Illustrative Mathematics
Running Around a Track I
The accuracy required by the design and measurement of an Olympic running track will surprise track stars and couch potatoes alike. Given a short introduction, the class then scaffolds into a detailed analysis of the exact nature of the...
Curated OER
Dilation
Tenth graders identidy and define various geometry terms, Students create exact replicas of a shape that is either smaller or larger than the original shape. Students prove that their entire shapes are larger or smaller in the same...
Curated OER
Cracks on the Walls
Students observe the cracks in school walls and pavements. In this geometry lesson, students explore the factors to be considered before building a structure. They complete a graphing and calculation worksheet after the lesson.