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Instructional Video3:31
Corbett Maths

Enlargements with Fractional Scale Factors

For Students 6th - 12th Standards
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...
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Assessment
Mathed Up!

Negative Scale Factor

For Students 9th - 12th
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...
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Instructional Video5:11
Corbett Maths

Enlargements with Negative Scale Factor

For Students 6th - 12th Standards
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...
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Lesson Plan
EngageNY

Scale Factors

For Students 9th - 10th Standards
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...
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Instructional Video6:31
Corbett Maths

Describing Enlargements

For Students 6th - 12th Standards
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.
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Assessment9:05
Mathed Up!

Enlargements

For Students 8th - 11th Standards
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...
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Instructional Video2:40
Corbett Maths

Enlargements

For Students 6th - 12th Standards
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...
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Instructional Video5:34
Corbett Maths

Enlargements Using Ray Method

For Students 8th - 11th Standards
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...
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Lesson Plan
EngageNY

Scale Drawings

For Students 9th - 10th Standards
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...
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Instructional Video4:55
Corbett Maths

Finding the Centre of Enlargement

For Students 6th - 12th Standards
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...
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Lesson Plan
EngageNY

Making Scale Drawings Using the Ratio Method

For Students 9th - 10th Standards
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. 
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Lesson Plan
Curated OER

Investigating Scale Factors with the Geometer's Sketchpad

For Teachers 7th - 12th
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...
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Worksheet
Curated OER

Geometry Worksheet 9.5: Rotational Symmetry

For Students 9th - 12th
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.
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Worksheet
Curated OER

Enlargement Worksheet

For Students 8th - 10th
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.
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Lesson Plan
Curated OER

How Big is Barbie?

For Teachers 9th - 12th
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...
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Worksheet
Curated OER

Six Exercise Sets on Transformations

For Students 8th - 11th Standards
Middle and high schoolers solve fifteen problems from six exercise sets covering transformations, reflections, rotations, and enlargements. The solutions are provided.
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Worksheet
Curated OER

Similarity

For Students 7th - 12th
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...
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Assessment
Inside Mathematics

Hopewell Geometry

For Teachers 9th - 12th Standards
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...
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Assessment3:06
Mathed Up!

Mixed Transformations

For Students 8th - 11th Standards
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...
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Worksheet
Curated OER

Unit 14 - Loci and Transformations

For Students 9th - 12th
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.
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Lesson Plan
Curated OER

Corresponding Parts of Similar Triangles

For Teachers 9th - 12th Standards
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...
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Lesson Plan
1
1
Illustrative Mathematics

Running Around a Track I

For Teachers 7th - 11th Standards
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...
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Lesson Plan
Curated OER

Dilation

For Teachers 10th
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...
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PPT
Curated OER

Endocrine System: Hormones

For Teachers 9th - 12th
The many images and labeled diagrams in this PowerPoint will help learners understand different areas of the endocrine system. The slide show starts with information about the absorption of lipid and protein based hormones, and then...