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Worksheet
Mt. San Antonio Collage

The Trapezoid

For Students 9th - 12th Standards
Enjoy this nicely organized worksheet that puts together multiple problems regarding trapezoid proofs. The resource can be used as a guide that begins with proving properties and ends with solving for measures of line segments.
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Worksheet
Curated OER

Euclidean Proofs involving Triangles and Circles (Congruency Proofs)

For Students 10th
In this geometry worksheet, 10th graders focus on Euclidean proofs involving triangles and circles.  The eight page worksheet contains eight proofs.  Solutions are not provided. 
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Worksheet
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Jesuit High School

Geometry Sample Problems

For Students 8th - 11th Standards
I'd like to prove that this worksheet has a lot to offer. Seven problems using triangles and parallelograms practice the traditional method of a two-column proof. After the worksheet is some practice problems that show worked out...
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Lesson Plan
2
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Illustrative Mathematics

Are They Similar?

For Teachers 9th - 11th Standards
Learners separate things that just appear similar from those that are actually similar. A diagram of triangles is given, and then a variety of geometric characteristics changed and the similarity of the triangles analyzed. Because the...
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Assessment
Inside Mathematics

Rhombuses

For Teachers 9th - 12th Standards
Just what does it take to show two rhombuses are similar? The assessment task asks pupils to develop an argument to show that given quadrilaterals are rhombuses. Class members also use their knowledge of similar triangles to show two...
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Worksheet
Curated OER

Circle Proofs

For Students 10th
In this circle proofs learning exercise, 10th graders complete 4 different problems that include circle proofs. They respond to each of the questions that deal with circle proofs. Then, students read the given information and use the...
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Interactive
Curated OER

Proofs with Triangles Self-check Practice

For Students 8th - 10th
In this triangle theorems worksheet, students identify the theorem used to prove the specified triangular relationship. Students are shown an illustration of two or more triangles. They identify the postulate that would be used to prove...
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Worksheet
Curated OER

Properties of Geometry

For Students 10th
In this properties of geometry worksheet, 10th graders solve and complete 12 different problems that include various theorems. First, they draw a figure that illustrates the SAS inequality property. Then, students prove that two line...
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Lesson Plan
Curated OER

NON-EUCLIDEAN GEOMETRY.

For Teachers 8th - 9th
Students study relationships between angles, side lengths, perimeters, areas and volumes of similar objects. In this lesson students also create and critique inductive and deductive arguments concerning congruency, similarity and the...
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Lesson Plan
Curated OER

The Pythagorean Theorem Lesson 2

For Teachers 8th - 12th
Learners discuss and review examples of the Pythagorean Theorem using a GSP, Geometer's Sketchpad, activity.
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Worksheet
Curated OER

Why do Stars Rise in the East?

For Students 8th - 10th
For this stars rise in the east worksheet, students use geometry to show how the Earth rotates from west to east and why celestial bodies appear to rise in the east and set in the west. Students draw a figure and label given points in...
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Worksheet
Mt. San Antonio Collage

Properties of a Parallelogram

For Students 9th - 12th Standards
More than just a worksheet, the resource provides a thorough guide to navigate through the land of parallelograms. Filled with definitions and theorems, the resource supports learners through problems such as proofs and finding missing...
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Lesson Plan
Curated OER

Pythagorean Theorem by Graphic Manipulation

For Teachers 7th - 9th
There are many different ways to show a proof of the Pythagorean Theorem.  Here is a nice hands-on paper cutting activity that shows a graphic representation. You can even challenge your young Pythagoreans to come up with their own...
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Lesson Plan
Curated OER

As the Bird Flies

For Teachers 7th - 8th
Students investigate the properties of lines and congruent triangle theorems as well as apply geometric properties and relationships to real-world mathematical problems. Given two different scenarios, they examine maps that have been...
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Activity
Illustrative Mathematics

Is This a Parallelogram?

For Teachers 9th - 12th Standards
If both pairs of opposite sides of a quadrilateral are congruent, is the quadrilateral a parallelogram? This task asks learners to determine the answer and to support their answer with a proof. The resource includes a commentary for...
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Activity
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Illustrative Mathematics

Midpoints of the Sides of a Paralellogram

For Teachers 9th - 12th Standards
This task asks learners to prove that the segment joining the midpoints of two sides of a parallelogram is both congruent and parallel to an adjacent side of the parallelogram. The activity would be good to use in a discussion about how...
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Lesson Plan
Curated OER

Rotation Symmetry

For Teachers 6th - 8th
Learners investigate the concept of symmetry by using various examples and performing independent practice with scaffolding provided by the teacher. They review reflection symmetry and cover the new rotation symmetry using manipuatives.
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Lesson Plan
Curated OER

Investigating AAS

For Teachers 9th - 10th
Students investigate the theorems of ASA, AAS, AAA and ASA. In this geometry lesson, students discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles are formed by two rays...
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Lesson Plan
Curated OER

Deductive and Inductive Reasoning

For Teachers 9th - 10th
Students differentiate between inductive and deductive reasoning. In this geometry lesson, students identify congruent figures and examine logos for congruency.
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Lesson Plan
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Cord Online

Pyramids and Cones

For Teachers 8th - 11th Standards
Young mathematicians find the surface area and volume of a square pyramid and a cone. In what looks like a typical activity out of a textbook, you'll find an activity where learners find an unknown measurement of a pyramid or cone,...
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Lesson Plan
Curated OER

THE MEAN INDEX CARD

For Teachers 6th - 8th
Students cut an index card to create three similar right triangles and explore the congruencies and proportions that exist. They investigate the properties of lines and concepts of congruency, similarity, tangency and symmetry of...
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Printables
Virginia Department of Education

High School Mathematics Geometry Vocabulary Word Wall Cards

For Teachers 9th - 10th
Having a good working knowledge of math vocabulary is especially important for geometry learners. Here are 119 pages worth of wonderfully constructed definitions, constructions, formulas, properties, theorems, and postulates. This is a...
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Lesson Plan
Curated OER

Why Doesn't SSA Work?

For Teachers 10th - 11th
Students investigate the relationship between angles and their sides. In this geometry lesson, students prove why SSA does not work as a true angle side relationship theorem.
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Unit Plan
Mathematics Vision Project

Circles: A Geometric Perspective

For Teachers 10th - 12th Standards
Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...