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Worksheet
Curated OER

Easy Worksheet: Classify the Triangle

For Students 9th - 12th
In this classify the triangle worksheet, learners 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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Worksheet
Curated OER

Geometry and Triangles

For Students 11th - Higher Ed
In this geometry triangles worksheet, students first determine how many degrees are found in one half and in three-fifths a revolution. Then they find the supplement of the two angles given and the radius of a circle. Students also...
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Worksheet
Curated OER

Isosceles Right Triangle

For Students 10th
In this isosceles right triangle worksheet, 10th graders solve and complete 5 different constructions of composition and decomposition. First, they make 4 congruent isosceles triangles with the model on the left. Then, students create...
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Worksheet
Curated OER

Triangle worksheets

For Students 10th
In this geometry worksheet, 10th graders explore triangle properties, including the sum of the measures of the angles of a triangle, the triangle inequalities, properties of isosceles triangles, properties of congruent triangles, and...
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Lesson Plan
Virginia Department of Education

Special Right Triangles and Right Triangle Trigonometry

For Teachers 9th - 11th Standards
Right triangles are so special! Use special right triangles to discover the trigonometric ratios. Pairs construct special right triangles and find the values of the ratios of the sides. In the process, they discover the ratios stay the...
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Lesson Plan
EngageNY

Congruence Criteria for Triangles—ASA and SSS

For Students 9th - 10th Standards
How do you know if a pair of triangles are congruent? Use the lesson to help class members become comfortable identifying the congruence criteria. They begin with an exploration of ASA and SSS criteria through transformations and...
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Lesson Plan
EngageNY

Triangle Congruency Proofs (part 2)

For Teachers 9th - 10th Standards
Looking to challenge your students that have mastered basic triangle congruence proofs? A collection of proofs employ previously learned definitions, theorems, and properties. Pupils draw on their past experiences with proofs to...
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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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Worksheet
Curated OER

Triangles and Quadrilaterals

For Students 10th
In this triangles and quadrilaterals worksheet, 10th graders solve 6 different problems related to using triangles and quadrilaterals in informal geometry. They determine how many lines of symmetry an equilateral triangle and an...
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Worksheet
Curated OER

Congruence of Triangles

For Students 10th
In this congruence of triangles worksheet, 10th graders solve and complete 10 different problems that include measuring the congruence of various triangles. First, they determine the length of a third side of an isosceles triangle. Then,...
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Lesson Plan
Curated OER

Geometric Properties

For Teachers 9th - 12th
Students find triangular angles using the angle theorem. In this geometry lesson, students describe labeled triangles, use the pythagorean theorem, and rewrite information about triangles in standard form.
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Assessment
Inside Mathematics

Circles in Triangles

For Teachers 9th - 12th Standards
Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...
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Worksheet
Curated OER

Coordinate Geometry Proofs

For Students 10th
For this coordinate geometry worksheet, 10th graders solve and draw 10 different problems related to complete proofs in coordinate geometry. First, they prove that a figure with given points is another figure by using slopes. Then,...
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Lesson Plan
Curated OER

Isosceles Triangle Investigation

For Teachers 9th - 12th
Students solve problems with isosceles triangles. In this geometry lesson, students identify and use the properties of triangles to solve their problems. They find the median, altitude, and angles to the triangles.
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Worksheet
Curated OER

Area and Perimeter

For Students 10th
In this area and perimeter worksheet, 10th graders solve and complete 18 various types of geometry problems. First, they find the area of a figure shown with consecutive sides perpendicular. Then, students find the area and perimeter of...
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Assessment
Inside Mathematics

Hopewell Geometry

For Teachers 9th - 12th Standards
The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...
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Unit Plan
Mathematics Vision Project

Module 5: Modeling with Geometry

For Students 9th - 12th Standards
Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts to finding...
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Worksheet
Curated OER

Find the Side of the Triangle

For Students 9th - 10th
In this geometry worksheet, students investigate the missing side of  triangles given the other two sides. There are 5 questions with a solution key.
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Worksheet
Curated OER

Easy Worksheet: Types of Triangles

For Students 9th - 12th
In this types of triangles worksheet, students solve 6 short answer problems. Students identify the type of triangle being described according to side length or angle measure.
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Worksheet
Curated OER

Isosceles Triangles Homework

For Students 9th - 10th
In this geometry instructional activity, students solve isosceles triangles using property of congruency. They find missing angles using the different angle theorem. There are 15 questions.
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Lesson Plan
Curated OER

Special Right Triangles

For Teachers 9th - 10th
Students identify different types of special right triangles. In this geometry lesson, students differentiate between right triangles and isosceles triangles. they construct the triangles using geometry software and make conjectures...
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Worksheet
Curated OER

Properties of Angles, Lines, and Triangles

For Students 10th
In this properties of angles, lines and triangles instructional activity, 10th graders solve and complete 28 different problems that include determining the measurement of various figures shown. First, they use the geometric properties...
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Lesson Plan
Curated OER

The Truth About Triangles And Proofs

For Teachers 9th - 12th
Students engage in a lesson plan that is about the classification of triangles and the mathematical proofs involved in working with them. They work on a variety of problems that are created by the teacher with the focus upon the...
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Worksheet
Curated OER

Congruent Triangles

For Students 10th
For this congruent triangles worksheet, 10th graders solve and complete 10 different problems that involve various congruent triangles. First, they determine the length of the third side given the other two. Then, students determine the...