EngageNY
Informal Proof of AA Criterion for Similarity
What does it take to show two triangles are similar? The 11th segment in a series of 16 introduces the AA Criterion for Similarity. A discussion provides an informal proof of the theorem. Exercises and problems require scholars to apply...
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Tessellation Trial and Error
In this interactive lesson, young scholars review attributes of equilateral polygons. They are introduced to the concept of a tessellation. Using protractors and pre-cut shapes, students arrange a variety of tiles to create...
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Congruent Triangles
In 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...
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Triangle Inequality Theorems Investigation
Learners estimate and measure triangles. For this geometry lesson, 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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Countdown Challenge: Triangle Inequality Theorem
In this triangle inequality worksheet, students test the Triangle Inequality Theorem. They measure the sides of given triangles, identify the type of triangle, and name angles in the triangle. The one-page worksheet contains 36 problems.
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The Pythagorean Theorem
There isn't a more popular geometry formula than the Pythagorean Theorem! Learners understand the special side relationships in a right triangle. They use the Pythagorean Theorem to find missing sides and to solve problems. They begin...
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Math Games for Skills and Concepts
A 27-page packet full of math games and activities builds on algebra, measurement, geometry, fractional, and graphing skills. Young mathematicians participate in math games collaboratively, promoting teamwork and skills practice.
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Triangle worksheets
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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Polygons Multiple Choice
For this geometry worksheet, learners identify the interior and exterior angles using the angle sum theorem. They identify and solve quadrilaterals using properties of quadrilaterals. There are 12 questions with an answer key.
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Got Complements? with Cabri Jr.
Learners use the axes and measure angle tool to explore and calculate complementary angles with Cabri Jr. They also identify what happens to the calculation as they drag the endpoint into a different quadrant. Finally, they label each...
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Indirect Proof and Inequalities in One Triangle
For this geometry worksheet, 10th graders order the sides and angles of a triangle and determine the range of the third side of a triangle given the lengths of two sides. The one page worksheet contains sixteen questions. Answers are...
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Geometric Concepts and Polygons
In this geometry learning exercise, students identify the altitude, perpendicular bisector, median, angle bisector and the area of different polygons. There are 33 problems.
National Security Agency
Classifying Triangles
Building on young mathematicians' prior knowledge of three-sided shapes, this lesson series explores the defining characteristics of different types of triangles. Starting with a shared reading of the children's book The Greedy Triangle,...
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Discover the Pythagorean Theorem
Middle schoolers explore the Pythagoras theorem. In this geometry lesson, students make right triangles and identify the parts of the triangle. Middle schoolers complete measurements of the sides of the triangle.
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Algebra and Trigonometry - Week 3: Story Problems
In this story problem worksheet, students read story problems, write equations, and solve. They use the law of sines, the law of cosines, the distance formula, and rates to solve problems. This two-page worksheet contains seven story...
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Chapter 6: Geometry Perimeter and Area
In this perimeter and area worksheet, students find the perimeter of various polygons. They compute the perimeter, surface area, circumference, and volume of given figures. Students explore trigonometric ratios. This twelve-page...
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Translating Transformations in Geometry
High schoolers create an image using given coordinates and evaluate how the coordinates change when a slide or rotation takes place.
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Algebra/Geometry Institute: Area of Polygons
Students find the area of polygons. In this area of polygons lesson, students find the area of parallelograms, rectangles, squares, and other polygons. They identify each given figure and determine the appropriate formula needed to...
CCSS Math Activities
Smarter Balanced Sample Items: High School Math – Claim 3
Communication is the key. A presentation provides 25 sample items for Claim 3, Communicating Reasoning, for the Smarter Balanced High School Math assessment. Items require pupils to answer the question and provide logical reasoning to...
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A Rectangle in the Coordinate Plane
A quadrilateral is drawn on the coordinate plane, and eighth grade geometers find the length of each side and the diagonals by applying the Pythagorean theorem.
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Quadrilaterals
In this geometry worksheet, 10th graders solve problems with quadrilaterals. They calculate the sum of the angles, find missing angles and identify properties of quadrilaterals. There are 16 questions with an answer key.
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Pythagorean Relationships
Oh that Pythagorean Theorem is so useful. Learners engage in a 45 minute learning activity that requires them to solve for missing angles and sides of a right triangle. They'll use the Pythagorean Theorem to find the rations of sides and...
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Triangles Congruency Theorems
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. In this geometry activity, 10th graders 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...
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Arc Length and Sectors
Find the length of an arc. Students relate central angles to the area and length of a sector and graph circles on the TI to make predictions.