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Worksheet
Curated OER

Triangle Fundamentals Homework

For Students 9th - 10th
In this geometry instructional activity, students identify the missing angles of non right triangles using the angle sum theorem. They solve for the unknown using algebra. There are 21 questions.
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Lesson Plan
Curated OER

The Search for Pythagoras' Treasure

For Teachers 8th - 10th
Students identify and define properties of triangles. In this geometry lesson, students identify the missing sides and angles of right triangles. They use the rules of the Pythagorean Theorem to solve their problems.
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Unit Plan
Curated OER

Connecting Algebra and Geometry Through Coordinates

For Teachers 9th - 10th Standards
This unit on connecting algebra and geometry covers a number of topics including worksheets on the distance formula, finding the perimeter and area of polynomials, the slope formula, parallel and perpendicular lines, parallelograms,...
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Unit Plan
Mathematics Vision Project

Module 6: Congruence, Construction, and Proof

For Teachers 8th - 10th Standards
Trace the links between a variety of math concepts in this far-reaching unit. Ideas that seem very different on the outset (like the distance formula and rigid transformations) come together in very natural and logical ways. This unit...
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Worksheet
Geometry Accelerated

Accelerated Geometry Review Sheet

For Students 8th - 10th Standards
Your geometry learners use their knowledge of various geometric concepts to write proofs. Starting with givens containing parallel line segments with transversals and triangles and quadrilaterals, and the mid-point and distance formulas;...
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Worksheet
Curated OER

Concurrent Lines, Medians and Altitudes

For Students 9th - 10th
In this geometry worksheet, students construct angles and identify medians and altitudes. They use a compass and protractor to perform heir construction. There are 28 questions.
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Lesson Plan
Curated OER

Investigating Trigonometric Ratios Through Similar Right Triangles.

For Teachers 8th - 10th
49Students investigate the properties of right triangles. In this geometry lesson, students differentiate between similar and congruent triangles. They use the Pythagorean Theorem to find the missing angles and sides.
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Lesson Plan
Curated OER

Exploring Geometric Mean

For Teachers 8th - 10th
Students solve problems using geometric means. In this geometry lesson, students create altitudes in right triangles. They use Cabri software to move the triangle around and observe different sides and angles.
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Lesson Plan
Curated OER

Exploring Geometric Mean

For Teachers 8th - 10th
Student identify the solution using geometric mean. In this geometry lesson, students create right triangles where the altitude of the triangle is the side containing the right angle. They modify shapes using Cabri software and observe...
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Handout
Lockport City School District

Reasons for Geometric Statement/Reason Proofs

For Students 8th - 11th Standards
Stuck trying to remember the formal language of a geometric proof? Never fear, this handout has them all ready to go. The reasons are sectioned by topic so this handy guide is ready when you are to tackle those two column proofs. 
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Worksheet
1
1
Jesuit High School

Geometry Sample Problems

For Students 8th - 11th Standards
I'd like to prove that this activity has a lot to offer. Seven problems using triangles and parallelograms practice the traditional method of a two-column proof. After the activity is some practice problems that show worked out solutions. 
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Lesson Plan
Curated OER

Studying Special Segments in Triangles

For Teachers 8th - 10th
Pupils investigate special segments in triangles. In this geometry lesson, students graph, compare, estimate and predict findings based on their data. They differentiate between similarity and congruence of triangles.
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Lesson Plan
Curated OER

Exploring Centers of a Triangle: Part 1

For Teachers 9th - 11th
Students use problem solving skills, formal geometry, and The Geometer?s Sketchpad. They model and solve two real-world problems by constructing the in center and circumcenter of triangles.
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Lesson Plan
Curated OER

Constructions of Isosceles and Equilateral Triangles

For Teachers 4th - 9th
Learners explore the difference between drawing and constructing a triangle utilizing The Geometer's Sketchpad on the computer. They create, develop and script constructions for both isosceles and equilateral triangles. Each student has...
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Lesson Plan
Curated OER

Plenty of Pythagoras

For Teachers 5th - 8th
Using a twelve foot knotted rope, students form a 3-4-5 right triangle. Following a discussion of observations about the lengths of the sides of the triangle, students use grid paper, scissors and a centimeter ruler to draw and measure...
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Unit Plan
Cuemath

Cuemath: Angle Bisector Theorem

For Students 9th - 10th Standards
This short lesson focuses more on the angle bisector theorem. Learn about the angle bisector theorem proof, triangle angle bisector theorem, how to construct angle bisector, and other interesting properties and facts around angle bisectors.
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Unknown Type
Khan Academy

Khan Academy: Solve Triangles: Angle Bisector Theorem

For Students 9th - 10th Standards
Use the Angle Bisector Theorem to find missing side lengths in triangles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
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Unknown Type
Khan Academy

Khan Academy: Solve Triangles: Angle Bisector Theorem

For Students 9th - 10th Standards
Use the angle bisector theorem to find missing side lengths in triangles.
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Unit Plan
CK-12 Foundation

Ck 12: Geometry: Angle Bisectors in Triangles

For Students 9th - 10th
[Free Registration/Login may be required to access all resource tools.] Apply angle bisector properties.
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Unit Plan
CK-12 Foundation

Ck 12: Geometry: Proportions With Angle Bisectors

For Students 9th - 10th
[Free Registration/Login may be required to access all resource tools.] Apply the fact that an angle bisector divides a triangle proportionally.
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Activity
Texas Instruments

Texas Instruments: Bisectors

For Teachers 9th - 10th
Students investigate the Perpendicular Bisector Theorem and examine its converse. They also explore the Angle Bisector Theorem.
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eBook
CK-12 Foundation

Ck 12: Interactive Geometry: 6.6 Theorems Involving Similarity

For Students 9th - 10th Standards
Learn the many theorems about triangles that you can prove using similar triangles.
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Handout
CK-12 Foundation

Ck 12: Geometry: Bisectors, Medians, Altitudes Study Guide

For Students 9th - 10th
This study guide on bisectors, medians, and altitudes covers key vocabulary, different theorems, and facts about the altitude and triangles. It is available for download with free registration.
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Handout
Geometry Help

Geometry Help: Lines and Angles

For Students 9th - 10th Standards
Explains the basic concept of lines and angles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.