Instructional Video3:26
CK-12 Foundation

Area and Perimeter of Similar Polygons: Lesson

7th - 11th
Find the square of the scale factor. A component of a large playlist on geometry discusses the ratios of the perimeters and areas of two similar polygons. The resource shows examples in finding the ratios that lead to a pattern.
Instructional Video2:07
CK-12 Foundation

SSS Similarity Theorem: Lesson

9th - 11th Standards
Judging by the sides, things appear similar. A portion of a larger playlist on geometry introduces the Side-Side-Side Similarity Theorem. The video shows how to use the lengths of sides to determine whether triangles are similar.
Instructional Video3:15
CK-12 Foundation

Similar Polygons and Scale Factors: Lesson

7th - 11th Standards
Develop an understanding of the scale of similarity. Starting with the concept of congruency, the resource introduces the idea of similarity between two figures. As part of a larger playlist on geometry, it defines similarity and uses...
Instructional Video4:36
CK-12 Foundation

Self Similarity: Lesson

8th - 11th
Zoom in to reveal more of the same. The resource introduces the concept of self similarity. Using a simple example, the video—part of a larger playlist covering geometry concepts—illustrates the meaning of a self similarity figure.
Instructional Video2:35
CK-12 Foundation

Triangle AA Similarity: Lesson

7th - 11th Standards
Two sets of congruent angles leads to three. Using diagrams of two triangles, the presentation intuitively shows that if two sets of angles are congruent, the third set is too. The portion of a geometry playlist uses that information to...
Instructional Video2:30
CK-12 Foundation

SAS Similarity Theorem: Lesson

7th - 11th Standards
When given two sides and an angle, make similar triangles. The video describes the SAS Similarity Theorem. Using the theorem, the segment of a larger geometry playlist determines whether two triangles are similar.
Instructional Video17:34
3Blue1Brown

Derivative Formulas Through Geometry | Essence of Calculus, Chapter 3

11th - Higher Ed
Geometry to the rescue. By watching a video, scholars see how geometric concepts help explain derivative formulas: areas of rectangles and volumes of rectangular prisms for the Power Rule and similarity and trig ratios for the Sine Rule.
Assessment9:05
Mathed Up!

Enlargements

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...
Instructional Video4:12
Curated OER

How Do You Find a Scale Factor in Similar Figures?

6th - 10th
Three angles of one triangle are equal to the corresponding angles in another triangle. Use a ratio of corresponding sides to find the scale factor. Actually, there are two scale factor values. The instructor will explain how to get both...
Instructional Video4:22
Curated OER

How Do You Solve a Problem Using Indirect Measurement with Shadows?

6th - 10th
Using indirect measurement, this video shows viewers how to find the height of a flagpole. The lecturer employs drawings as well as proportions to solve this problem, explaining each step. A useful resource to aid struggling learners and...
Instructional Video4:57
Curated OER

How Do You Solve a Problem Using Indirect Measurement with Shadows?

6th - 12th
Using indirect measurement, this video shows viewers how to find the height of a flagpole. The lecturer employs drawings as well as proportions to solve this problem, explaining each step. A useful resource to aid struggling learners and...
Instructional Video4:48
Curated OER

How Do You Find a Scale Factor in Similar Figures?

6th - 12th
Three angles of one triangle are equal to the corresponding angles in another triangle. Use a ratio of corresponding sides to find the scale factor. Actually, there are two scale factor values. The instructor will explain how to get both...
Instructional Video7:22
Curated OER

What are Similar Figures?

6th - 8th
Similar figures have the same shape, the same corresponding angles, but different lengths of their corresponding sides. The teacher explains just what all that means. She demonstrates how to compare the two shapes to prove they are similar.
Instructional Video5:44
Curated OER

How Do You Find Missing Measurements of Similar Figures Using a Scale Factor?

6th - 8th
Similar figures have corresponding sides and corresponding angles. With this in mind, missing values can be found by using a scale factor. Not sure how to do that? Watch this video as the instructor illustrates how to set up the known...
Instructional Video7:31
Curated OER

How Do You Identify Corresponding Parts in Congruent Triangles?

6th - 10th
Congruent, corresponding, congruent corresponding. If two figures are congruent, then their corresponding sides and corresponding angles are congruent. Is this to be believed? Watch this video and see if the proof is in the pudding.
Instructional Video6:22
Curated OER

How Do You Find Missing Measurements of Similar Figures Using a Proportion?

6th - 8th
Two similar triangles have the same angles, but their legs have different lengths. This means their angles are congruent, and thusly, their corresponding sides are congruent. So there is a missing measurement that needs to be found. Set...
Instructional Video1:25
Curated OER

Proportions and Similar Figures

5th - 8th
Duane demonstrates how to find a missing length in figures that are similar. In this example he uses two similar triangles.
Instructional Video
Loyola University Chicago

Math Flix: Proportion Similar Figures

6th - 8th Standards
This QuickTime movie applies the concept of proportion to similar geometric figures. As you watch and listen to the teacher and students interact it helps clarify the thinking behind applying this concept. Allow loading time.
Instructional Video
Sophia Learning

Sophia: In Group/out Group: Relationships and Attitudes: Lesson 3

9th - 10th
At the end of this tutorial, the learner will understand ways in which group membership affects people's perceptions and actions towards their own and other groups. It is 3 of 3 in the series titled "In-Group/Out-Group: Relationships and...
Instructional Video
Sophia Learning

Sophia: Scale Factors: Lesson 5

9th - 10th
This lesson defines the phrase scale factor. It is 5 of 5 in the series titled "Scale Factors."
Instructional Video
Sophia Learning

Sophia: Why and How Do Humans Group?: Lesson 3

9th - 10th Standards
At the end of this tutorial, the learner will understand causes and dynamics of group formation. It is 3 of 3 in the series titled "Why and How do Humans Group?."
Instructional Video
Khan Academy

Khan Academy: Worked Examples: Geometry: Ca Geometry: Similar Triangles 1

9th - 10th
In this video tutorial students explore a proof using similar triangles.
Instructional Video
Khan Academy

Khan Academy: Triangles: Finding Area Using Similarity and Congruence

9th - 10th Standards
Explains how to determine the area of a pentagonal shaded region in a triangle. The triangle that is broken into multiple similar and congruent triangles.
Instructional Video
Sophia Learning

Sophia: Similar Solids

6th - 8th
Explore how objects can have the same shape but not the same size and how they are categorized as similar solids. Assess learning with a quiz.