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Worksheet
Curated OER

Classifying Triangles

For Students 8th - 10th
In this classifying triangles worksheet, students explore given lengths or angle measurements and then classify each triangle as isosceles, scalene or equilateral. They also determine if the triangle may be right, acute or obtuse. This...
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Interactive
CK-12 Foundation

Pythagorean Theorem to Classify Triangles: Missing Angles

For Students 8th - 12th Standards
Learn to use the Pythagorean Theorem with non-right triangles. Pupils use the interactive to discover the relationship between the lengths of sides for acute and obtuse triangles. They compare the squares of the sides of the triangles to...
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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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Lesson Plan
Alabama Learning Exchange

What You Know About the Bermuda Triangle?

For Teachers 9th - 12th Standards
Get lost in the classifications. Using the backdrop of the Bermuda Triangle, pupils classify it by angle and side measures. They also learn information about the triangle and its history.
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Worksheet
Curated OER

Classifying Triangles

For Students 10th
For this classifying triangles worksheet, 10th graders solve 12 different problems that include classifying various types of triangles. They classify and then identify each of the given triangles as isosceles, scalene, or equilateral....
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Lesson Plan
Curated OER

Triangle Inequality Theorems Investigation

For Teachers 9th - 10th
Students estimate and measure triangles. In this geometry instructional activity, students identify the relationship between three sides and a triangle. They use the inequality theorem to decide if a triangle will be formed or not.
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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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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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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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Worksheet
Curated OER

Easy Worksheet: Classify the Triangle

For Students 9th - 12th
In this classify the triangle worksheet, students solve 6 short answer problems. Students identify the type of triangle being described according to its angle measures and side lengths.
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Lesson Plan
Curated OER

Exploring Geometric Figures

For Teachers 10th
Tenth graders explore mathematics by participating in hands-on daily activities. Learners identify a list of different shapes and classify them by shape, size, sides and vertices. They utilize tangrams and geometric pieces to gain an...
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Lesson Plan
Curated OER

Triangle Inequality Theorem

For Teachers 8th - 10th
Students use the inequality theorem to solve triangles and their properties. In this geometry lesson, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary length needed to make a...
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Worksheet
Curated OER

Informal Geometry

For Students 8th - 12th
Middle and high schoolers solve and complete 29 various types of problems. First, they match each name with its correct formula. Then, students find the length of the missing side and the distance between the two points given. In...
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Lesson Plan
Curated OER

Connecting Formulas Related to Geometric Figures

For Teachers 8th - 12th
Young scholars identify diagrams of quadrilaterals and circles by different names and classify the figures. They name the areas for each diagram and practice solving the formulas for each.
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Lesson Plan
Curated OER

Review of Triangles

For Teachers 8th - 10th
Students investigate the Pythagorean Theorem. In this geometry lesson, students define angles and sides of right triangles. They calculate the area and surface area using formulas derived by the Pythagorean Theorem.
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Interactive
CK-12 Foundation

Polygon Classification

For Students 8th - 10th
Polly want a polygon? Young mathematicians sort shapes using an interactive. They classify the shapes as convex polygons, concave polygons, or not polygons.
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Lesson Plan
Curated OER

Triangle Classification

For Teachers 9th - 12th
High schoolers classify different types of triangles. In this geometry lesson, students identify and use properties of triangles. They differentiate between isosceles and equilateral triangles.
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Lesson Plan
Curated OER

Triangles in My Life

For Teachers 10th
Tenth graders investigate where in the real world triangles are used. In this geometry lesson, 10th graders write an essay describing where in their lives triangles are used. They can use food, buildings, clothing or anything triangular...
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Worksheet
Curated OER

Special Segments is a Triangle

For Students 10th
In this geometry worksheet, 10th graders examine the special segments that occur in a triangle.  The three page worksheet contains twenty-five problems.  Answers are not included. 
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Lesson Plan
Curated OER

Geometry Jeopardy

For Teachers 9th - 11th
Students identify the pattern in a problem. In this geometry lesson, students make predictions, collect and analyze data. They apply the idea of scales and measurements to the real world.
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Lesson Plan
Curated OER

Pythagorean Theorem

For Teachers 9th - 12th
Students are introduced to the Pythagorean theorem. They use three different activities that give students the opportuntiy to observe triangles, and use the Pythagorean theorem and practice different ways of determining areas of...
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Worksheet
Mt. San Antonio Collage

Postulates, Angles, and Their Relationships

For Students 8th - 11th Standards
More than a worksheet, learners go through geometry topics example by example on the nicely organized handout. From postulates to classifying angles, there are rules and examples provided for each topic. The ten pages of problems provide...
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Worksheet
Curated OER

Properties and Attributes of Polygons

For Students 10th
For this geometry worksheet, 10th graders determine if a polygon is convex or concave and apply the polygon Angle sum theorem and the polygon exterior angle sum theorem to determine the measures of interior and exterior angles of a...
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Worksheet
Curated OER

Points of Concurrency for Triangles

For Students 10th
In this geometry worksheet, 10th graders solve a  problem involving the possible lengths for the third side of a triangle given two sides and determine where the point of concurrency lies in relation to the triangle. The one page...