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Isosceles Triangle

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  • Isosceles Triangle Lesson Plans
  • Cut or Count the Triangles
  • Base Angles Theorem
  • Base Angles
  • Triangle Sum Theorem

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Isosceles Triangle Teacher Resources

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Find Isosceles Triangle lesson plans and worksheets
Showing 377 resources
24 Items in Unit
Geometry Unit 4: Triangle Congruence
Lesson Planet Curated

Geometry Unit 4: Triangle Congruence

For Teachers 9th - 12th Standards
The Geometry Unit 4: Triangle Congruence unit module contains five lessons—each with a video, teacher reference, practice packets, solutions, and corrective assignments. To begin, scholars review the types of triangles, then investigate...
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12 Items in Course
Flipped Math: Geometry
Lesson Planet Curated

Flipped Math: Geometry

For Students 9th - 12th Standards
Imagine taking a complete geometry course remotely! Eleven units make up the My Geometry course. Each unit follows the Flipped-Mastery cycle of learning, divided into two semesters. Pupils watch and take notes on a video that details the...
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12 Items in Topic
Math Antics Geometry Video Lessons
Lesson Planet Curated

Math Antics Geometry Video Lessons

For Teachers 4th - 8th Standards
The point of this collection of 12 videos is to introduce learners to three basic parts of geometry—points, lines, and planes. The presenter provides definitions, shows how to classify shapes, provides examples, and shows how to use...
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29 Items in Unit
Geometry Unit 1: Tools for Geometry
Lesson Planet Curated

Geometry Unit 1: Tools for Geometry

For Teachers 9th - 12th Standards
Six resources make up the first unit in the Flipped-Mastery series for geometry. In the first lesson, scholars learn how to identify and name points, lines, and planes. They work with four postulates, then practice the skills for naming...
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Instructional Video3:02
Isosceles Triangles: Lesson Instructional Video
CK-12 Foundation

Isosceles Triangles: Lesson

For Students 8th - 11th Standards
Two sides give us two angles. A segment of a playlist on basic geometry revisits isosceles triangles. The presentation explains several properties and theorems related to isosceles triangles.
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PPT
Isosceles Triangles PPT
Curated OER

Isosceles Triangles

For Teachers 4th - 5th
In need of a fun way to define an isosceles triangle? This activity has learners fold a paper in half and then cut it to create an isosceles triangle. They determine the line of symmetry by folding the triangle in half and then use the...
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Instructional Video6:29
Pythagoras Rectangles and Isosceles Triangles Instructional Video
Corbett Maths

Pythagoras Rectangles and Isosceles Triangles

For Students 7th - 12th Standards
When does the Pythagorean Theorem come in handy? An intriguing video uses the Pythagorean Theorem to solve problems other than simply finding the length of a side of a right triangle. Pupils find the diagonal of a rectangle and the...
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Instructional Video4:28
How Do You Find Missing Angles in an Isosceles Triangle? Instructional Video
Curated OER

How Do You Find Missing Angles in an Isosceles Triangle?

For Teachers 6th - 8th
Finding the missing values of two angles in an isosceles triangle is not as difficult as it sounds. But how can two out of three angle's measurements be found? Well, there are special properties about an isosceles triangle which make...
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Instructional Video3:40
How Do You Find Missing Angles in an Isosceles Triangle Using Right Triangles? Instructional Video
Curated OER

How Do You Find Missing Angles in an Isosceles Triangle Using Right Triangles?

For Teachers 6th - 8th
Given an isosceles triangle, and the value of one angle, find the missing values. There are some special properties about isosceles triangles. Use the triangle sum theorem to solve this problem. Watch this video to see how the instructor...
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Lesson Plan
Geometry Journal:  Isosceles Triangles Lesson Plan
Curated OER

Geometry Journal: Isosceles Triangles

For Teachers 10th - 12th
In this isosceles triangles worksheet, students justify and determine the symmetry of an isosceles triangle. They explore the bisector of rectangles. This three-page worksheet contains two problems. Answers are listed on page three.
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Lesson Plan
Isosceles Triangle Theorem Lesson Plan
Curated OER

Isosceles Triangle Theorem

For Teachers 8th - 10th
In this geometry worksheet, students differentiate between regular triangles and isosceles triangles. They apply the converse theorem and the vertex angle. There are eleven questions with an answer key.
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Worksheet
Isosceles Triangles and Special Line Segments Worksheet
Mt. San Antonio Collage

Isosceles Triangles and Special Line Segments

For Students 9th - 12th Standards
Under which conditions can a triangle be classified as isosceles? High schoolers practice identifying isosceles triangles and special line segments, including angle bisectors, medians of triangles, and perpendicular bisectors of sides of...
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Lesson Plan
Base Angles of Isosceles Triangles Lesson Plan
EngageNY

Base Angles of Isosceles Triangles

For Students 9th - 10th Standards
Build confidence in proofs by proving a known property. Pupils explore two approaches to proving base angles of isosceles triangles are congruent: transformations and SAS. They then apply their understanding of the proof to more complex...
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Instructional Video7:11
The Isosceles Triangle Theorem is Actually Really Simple! Instructional Video
Krista King Math

The Isosceles Triangle Theorem is Actually Really Simple!

For Students 9th - 12th Standards
The isosceles triangle comes with its own set of properties. A lecturer shows how to apply the Isosceles Triangle Theorem to find missing side lengths or angle measures. The final example involves both square roots and quadratic...
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Instructional Video
SAT Prep: Test 1 Section 9 Part 3 Instructional Video
Khan Academy

SAT Prep: Test 1 Section 9 Part 3

For Students 9th - 12th
If it takes a long time to complete the problems on the math SAT, it doesn't matter if they are correct - the problems that are left over will count against the student's score. Sal takes care to show quicker ways to complete problems...
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Lesson Plan
How many isosceles Triangles Can You Find? Lesson Plan
Curated OER

How many isosceles Triangles Can You Find?

For Teachers 5th
Fifth graders solve problems while examining a variety of isosceles triangles.  In this isosceles triangle lesson, 5th graders examine shapes to find their characteristics.  Students pay particular attention to the...
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Lesson Plan
How many isosceles triangles can you find? Lesson Plan
Curated OER

How many isosceles triangles can you find?

For Teachers 7th
Seventh graders recognize the characteristics of isosceles triangles. In this isosceles triangle lesson, 7th graders use geoboards to create isosceles triangles. Students record results and explain why they have an isosceles triangle.
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Lesson Plan
Geometry Regents Questions: Isosceles Triangle Theorem Lesson Plan
Curated OER

Geometry Regents Questions: Isosceles Triangle Theorem

For Teachers 9th - 12th
For this isosceles triangle worksheet, high schoolers solve 19 multiple choice and short answer problems.  Students use the isosceles triangle theorem to determine unknown angle measures.
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Worksheet
Isosceles Triangles Worksheet
Curated OER

Isosceles Triangles

For Students 9th - 12th
In this geometry worksheet, students set up equations to solve for the missing angle or side of an isosceles triangle. All the equations turn out to be linear and not quadratic. There are 15 questions. 
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Lesson Plan
Sea Squares Lesson Plan
Curated OER

Sea Squares

For Teachers 10th
In this sea squares worksheet, 10th graders solve 5 different problems that include various geometrical figures. First, they draw a number line using one color. Then, students draw 2 obtuse angles and 3 isosceles triangles with different...
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Worksheet
2D Shape Sheet Isosceles Triangles Worksheet
Math Salamanders Ltd.

2D Shape Sheet Isosceles Triangles

For Students 3rd - 4th Standards
In this isosceles triangle activity, students cut or count the triangles on this sheet. Students cut or count out 13 isosceles triangles that are all different colors.
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Lesson Plan
Isosceles Triangles Lesson Plan
Curated OER

Isosceles Triangles

For Teachers 9th - 10th
Students identify the properties of an isosceles triangle. In this geometry activity, students find the midpoint, median and angle bisector of a triangle. They construct angle bisectors and measure missing angles.
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Lesson Plan
Isosceles Triangles Lesson Plan
Curated OER

Isosceles Triangles

For Teachers K - 2nd
Students investigate triangles. In this shapes geometry instructional activity, students define and state the attributes for equilateral, scalene, and isosceles triangles. Students locate the prefix "tri" in a variety of words and make...
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Worksheet
The Isosceles Triangle Problem Worksheet
Curated OER

The Isosceles Triangle Problem

For Students 10th
In this geometry worksheet, 10th graders solve a problem involving an isosceles triangle.  The problem appears to be deceptively easy, but instead requires the use of trigonometry to arrive at a correct solution.  The one page...
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