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31 reviewed resources

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Other Resource Types (31)
Lesson Planet

How Much Proof Do We Need?

For Teachers 9th - 12th Standards
Are two angles enough? Given two triangles, the class determines through the definition of similarity and transformations whether the two triangles are similar. Provided with pairs of triangles and measurements, small groups find out...
Lesson Planet

How Tall is the Tree?

For Teachers 9th - 12th Standards
Pairs or small groups work together to determine the height of a tree using similar triangles. Learners make a judgement which direction to let a tree fall to avoid hitting any structures. They then write letters to the principal...
Lesson Planet

Module 4: Similarity and Right Triangle Trigonometry

For Teachers 9th - 12th Standards
Right you are to use a great resource. Starting with a lesson on dilations, scholars learn about similarity transformations and similar triangles. They use the knowledge to develop an understanding of right triangle trigonometry in later...
2:35
Lesson Planet

Triangle AA Similarity: Lesson

For Students 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...
Lesson Planet

Parametric Equations and a Heart

For Students 8th - 12th Standards
Trigonometry, art, and Valentine's Day come together in a creative activity about parametric equations. Learners calculate several equations before graphing them either by hand, on a graphic calculator, or Excel spreadsheet to curve...
Lesson Planet

Prove the AA Similarity Theorem

For Students 9th - 12th Standards
Transform a diagram into a proof. Given two triangles on a coordinate plane, pupils develop a proof to show they are similar. The learners use the fact that two angles of one triangle are congruent to two angles of another and their...
Lesson Planet

Justifying a Proof of the AA Similarity Theorem

For Students 9th - 12th Standards
Why are two triangles with congruent angles similar? Class members provide the justifications or explanations of the steps of a proof of the AA Similarity Theorem. The proof uses transformations as a basis to proving the theorem.
Lesson Planet

Describe the AA Similarity Theorem

For Students 9th - 12th Standards
Assess the ability to apprehend AA. The short assessment determines whether class members understand the Angle-Angle Similarity Theorem. Pupils write the theorem and identify the assumptions and the conclusion within it. The scholars...
Lesson Planet

Similar Triangles

For Teachers 9th - 11th Standards
Pupils work in pairs to investigate what it takes to prove that two triangles are similar. They work through various shortcuts to find which are enough to show a similarity relationship between the triangles. Small groups work with the...
Lesson Planet

Modeling Motion: Rolling Cups

For Students 9th - 12th Standards
Connect the size of a rolling cup to the size of circle it makes. Pupils view videos of cups of different sizes rolling in a circle. Using the videos and additional data, they attempt to determine a relationship between cup measurements...
Lesson Planet

Solving Problems with Circles and Triangles

For Teachers 9th - 12th Standards
After completing a task involving examining the ratio of areas of triangles and circles in a given figure, scholars examine sample responses to identify other strategies they could use to solve the problem.
1 In 1 Collection
EngageNY

Similarity

For Students 9th - 10th Standards
Learn similarity through a transformations lens! Individuals examine the effects of transformations and analyze the properties of similarity, and conclude that any image that can be created through transformations is similar. The...
1 In 1 Collection
EngageNY

Mid-Module Assessment Task - Geometry (Module 2)

For Students 9th - 10th Standards
Challenge: create an assessment that features higher level thinking from beginning to end. A ready-made test assesses knowledge of dilations using performance tasks. Every question requires a developed written response. 
1 In 1 Collection
EngageNY

How Far Away Is the Moon?

For Students 9th - 10th Standards
Does the space shuttle have an odometer? Maybe, but all that is needed to determine the distance to the moon is a little geometry! The lesson plan asks scholars to sketch the relationship of the Earth and moon using shadows of an...
1 In 1 Collection
EngageNY

Families of Parallel Lines and the Circumference of the Earth

For Students 9th - 10th Standards
How do you fit a tape measure around the Earth? No need if you know a little geometry! Pupils begin by extending their understanding of the Side Splitter Theorem to a transversal cut by parallel lines. Once they identify the proportional...
1 In 1 Collection
EngageNY

The Side-Angle-Side (SAS) and Side-Side-Side (SSS) Criteria for Two Triangles to Be Similar

For Students 9th - 10th Standards
Playing with mathematics can invoke curiosity and excitement. As pupils construct triangles with given criteria, they determine the necessary requirements to support similarity. After determining the criteria, they practice verifying...
1 In 1 Collection
EngageNY

Between-Figure and Within-Figure Ratios

For Teachers 9th - 10th Standards
Tie the unit together and see concepts click in your young mathematicians' minds. Scholars apply the properties of similar triangles to find heights of objects. They concentrate on the proportions built with known measures and solve to...
1 In 1 Collection
EngageNY

The Angle-Angle (AA) Criterion for Two Triangles to Be Similar

For Teachers 9th - 10th Standards
What do you need to prove triangles are similar? Learners answer this question through a construction exploration. Once they establish the criteria, they use the congruence and proportionality properties of similar objects to find...
1 In 1 Collection
EngageNY

Properties of Similarity Transformations

For Teachers 9th - 10th Standards
You can explain it, but can you do it? After learners view a sequence of transformations, the next logical step is creating the transformation. Challenge your classes to construct a composition of transformations and verify the...
1 In 1 Collection
EngageNY

Similarity and the Angle Bisector Theorem

For Teachers 9th - 10th Standards
Identifying and verifying reproducible patterns in mathematics is an essential skill. Mathematicians identify the relationship of sides when an angle is bisected in a triangle. Once the pupils determine the relationship, they prove it to...
1 In 1 Collection
EngageNY

What Are Similarity Transformations, and Why Do We Need Them?

For Students 9th - 10th Standards
It's time for your young artists to shine! Learners examine images to determine possible similarity transformations. They then provide a sequence of transformations that map one image to the next, or give an explanation why it is not...
Lesson Planet

Similarity through Transformations

For Teachers 9th - 12th Standards
Create the ultimate miniature golf course. The 93-page model curriculum unit from the Massachusetts Department of Elementary and Secondary Education contains nine lessons on understanding similarity in terms of both Euclidean geometry...
Lesson Planet

Analytic Geometry Study Guide

For Students 9th - 12th Standards
Are you looking for a comprehensive review that addresses the Common Core standards for geometry? This is it! Instruction and practice problems built specifically for standards are included. The material includes geometry topics from...
Lesson Planet

Seven Circles III

For Teachers 9th - 11th Standards
A basic set-up leads to a surprisingly complex analysis in this variation on the question of surrounding a central circle with a ring of touching circles. Useful for putting trigonometric functions in a physical context, as well as...