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Prove the Pythagorean Theorem Using Similarity
Amaze your classes with the ability to find side lengths of triangles immediately — they'll all want to know your trick! Learners use the Pythagorean Theorem and special right triangle relationships to find missing side lengths.
Mathed Up!
Sine and Cosine Rules and Area of Triangles
Learners discover how to find missing sides and angles using trigonometry. Scholars first watch a video covering the Law of Sines and Cosines, as well as the area formula for a triangle. To test their knowledge, they complete a worksheet...
Curated OER
Trigonometric Functions of Acute Right Triangles
Students derive the six trigonometric functions. In this trigonometry lesson, students show their understanding of trigonometric functions as they relate the right triangles. They find the missing angles and side use trig ratios of sine,...
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Triangle Sum Theorem
Teach your class how to solve problems using the triangle sum theorem. In this geometry lesson, students identify the missing angles in a triangle using the sum theorem. They graph triangles on the TI and moves the sides around to create...
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Geometry Worksheet- Angle
In this geometry worksheet, students solve questions dealing with angles, triangles, and quadrilaterals. They calculate the missing angle. There are 2 questions.
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More About Similar Triangles
Determine whether two triangles are similar. The lesson presents opportunities for pupils to find the criterion needed to show that two triangles are similar. Scholars use the definition of similarity to find any missing side...
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Right Triangle Trigonometry
In this geometry worksheet, 10th graders use right triangle trigonometry to find the missing angle measure. The two page worksheet contains fourteen problems. Answers are provided.
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Finding Angles in Right Triangles
In this geometry worksheet, 10th graders use right triangle trigonometry to solve application problems in which they find the measure of the missing angle in a right triangle. The two page worksheet contains five free response...
Mathed Up!
Angles in Triangles and Quadrilaterals
This short video show viewers how to connect the sum of the angles in a triangle to other angle measurements. Pupils determine the missing measures for angles involved with triangles and quadrilaterals. Class members then must explain...
Curated OER
Determine the Measure of an Angle of a Right Triangle.
In this geometry worksheet, students solve word problems by finding the values of missing angles and missing sides of triangles. They review their trigonometric properties of a right triangle. There are 9 problems with an answer key.
Curated OER
Indirect Measurement with Similar Triangles
Young scholars use similar triangles to find missing heights. In this using similar triangles to find missing heights lesson, students use proportions to find the heights of missing side lengths. Young scholars find the...
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Angles in Polygons
For this angles in polygons worksheet, learners determine the value of a missing angle measure. They find the value of interior angles and exterior angles. Polygons include triangles, quadrilaterals, pentagons, and hexagons. This...
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Isosceles Triangles
In this geometry worksheet, high schoolers set up equations to solve for the missing angle or side of an isosceles triangle. All the equations turn out to be linear and not quadratic. There are 15 questions.
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Exploring Angle/Pair Relationships
Students find missing angles and sides of triangles. In this geometry lesson, students create intersecting lines to measure angles. They use Cabri Software to create virtual angles.
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Mixed Right Triangles
In this geometry learning exercise, 10th graders use right triangle trigonometry to find the missing angle measure or side length in right triangles. The one page interactive learning exercise contains ten questions. Answers and hints...
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You Can't Go Wrong with a Right Triangle 1
Fourth and fifth graders study the Pythagorean Theorem and apply it to find the missing side of a right triangle.
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Trigonometric Triangles
In this trigonometry worksheet, students find the missing angle and sides given the 6 trigonometric values. There are 6 questions with an answer key.
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Geometric Figure Quiz
In this geometric figure worksheet, students answer 10 multiple choice questions about geometric figures. Students find missing angles, interior angles, properties of polygons, etc.
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Missing Angle Problems
In this problem solving worksheet, 6th graders focus on the angles described in each word problem. Students must solve for each of the 6 problems, giving a written explanation for each in the space provided.
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Special Segments in a Triangle
In this geometry worksheet, 10th graders review the vocabulary associated with the special segments of a triangle and the associated points of concurrency and solve problems in which they find the indicated missing angle or...
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The Triangle Midsegment Theorem
For this geometry worksheet, 10th graders identify the vocabulary associated with the Triangle Midsegment Theorem and solve problems in which they find the size of a missing angle or segment. The one page worksheet contains...
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Area Measures and Right Triangles
Your class will investigate the relationship among different triangles. This geometry lesson, demonstrates how to make a connection between triangles and the Pythagorean Theorem. They identify the missing side or angle of a triangle.
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Law of Sines
Prove the Law of Sines two ways. The ninth segment in a series of 16 introduces the Law of Sines to help the class find lengths of sides in oblique triangles. Pupils develop a proof of the Law of Sines by drawing an altitude and a second...
Curated OER
Lines and Angles
In this lines and angles worksheet, students identify parallel and perpendicular lines. They demonstrate the characteristics of a straight line. They determine missing angle measurements. This two-page worksheet contains 3 multi-step...