CK-12 Foundation
Solving Equations Using the Pythagorean Theorem: Cryptography
Don't keep this resource a secret. Individuals learn to use the Pythagorean Theorem to find Pythagorean triples. They also see how Pythagorean triples can be useful in the field of cryptography to encrypt secret messages.
CK-12 Foundation
Lengths of Triangle Sides Using the Pythagorean Theorem: Find the Missing Side
What is the relationship between the sides of a right triangle? Learners use an interactive to create models of right triangles and view the relationship between the lengths of the sides. They finish by using the Pythagorean Theorem to...
EngageNY
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.
Willow Tree
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...
EngageNY
The Pythagorean Theorem
Class members explore the estimation of irrational numbers in association with the Pythagorean Theorem. The first activity of this module challenges pupils to use the Pythagorean Theorem to find unknown side lengths. When the length is...
EngageNY
Proof of the Pythagorean Theorem
What does similarity have to do with the Pythagorean Theorem? The activity steps through the proof of the Pythagorean Theorem by using similar triangles. Next, the teacher leads a discussion of the proof and follows it by an animated...
EngageNY
Applications of the Pythagorean Theorem
Begin seeing the world through the lens of geometry! Use the 19th installment in a 25-part module to apply the Pythagorean Theorem to solve real-world problems. Individuals sketch situations resulting in right triangles such as the...
EngageNY
Informal Proof of the Pythagorean Theorem
Prove the Pythagorean Theorem using multiple informal proofs. Scholars first develop an understanding of the origins of the Pythagorean Theorem through proofs. They round out the lesson plan by using the theorem to find missing side...
CK-12 Foundation
Pythagorean Theorem to Classify Triangles: Missing Angles
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...
EngageNY
Pythagorean Theorem, Revisited
Transform your pupils into mathematicians as they learn to prove the popular Pythagorean Theorem. The 16th lesson in the series of 25 continues by teaching learners how to develop a proof. It shows how to prove the Pythagorean Theorem...
EngageNY
Converse of the Pythagorean Theorem
Discover a new application of the Pythagorean Theorem. Learners prove and apply the converse of the Pythagorean Theorem in the 17th lesson in a 25-part series. The examples ask learners to verify right triangles using the converse...
EngageNY
Applications of the Pythagorean Theorem
Examine the application of the Pythagorean Theorem in problem-solving questions. Pupils apply the theorem to find lengths when given different scenarios. They finish the 17th installment in an 18-part series by applying the theorem...
EngageNY
Trigonometry and the Pythagorean Theorem
Ancient Egyptians sure knew their trigonometry! Pupils learn how the pyramid architects applied right triangle trigonometry. When comparing the Pythagorean theorem to the trigonometric ratios, they learn an important connection that...
Charleston School District
Pythagorean Theorem and Converse
You've heard that it is true, but can you prove it? Scholars learn the Pythagorean Theorem through proof. After an overview of proofs of the theorem, learners apply it to prove triangles are right and to problem solve. This is the second...
Charleston School District
Applications of the Pythagorean Theorem
Use patterns to your advantage! The Pythagorean Theorem allows learners to find missing sides of right triangles. Problems include those with both rational and irrational lengths.
EngageNY
The Converse of the Pythagorean Theorem
Is it a right triangle or not? Introduce scholars to the converse of the Pythagorean Theorem with a lesson that also provides a proof by contradiction of the converse. Pupils use the converse to determine whether triangles with given...
Charleston School District
3D Applications of the Pythagorean Theorem
How many right triangles can you find in a prism, cone, or pyramid? Using right triangles to find lengths in three-dimensional figures is the focus of the lesson. After working with the Pythagorean Theorem to find missing side...
Curated OER
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.
Flipped Math
Pythagorean Theorem and Its Converse
Make sure it is all right in class. Pupils review the Pythagorean Theorem and find sides of right triangles, either by simplifying radicals or using calculators to find approximate lengths. Learners find out how to use the converse to...
Virginia Department of Education
Pythagorean Theorem
Investigate the meaning of the Pythagorean Theorem through modeling. After comparing the area of the square of each side, individuals cut triangles and squares to facilitate the comparison.
Inside Mathematics
Patterns in Prague
Designers in Prague are not diagonally challenged. The mini-assessment provides a complex pattern made from blocks. Individuals use the pattern to find the area and perimeter of the design. To find the perimeter, they use the Pythagorean...
CK-12 Foundation
Pythagorean Theorem to Determine Distance: Tree Shadows
Why is that shadow getting longer? Determine the changes in the length of a shadow as the sun changes position in the sky. Individuals use an interactive to calculate the length of a shadow at different times during the day via the...
Shodor Education Foundation
Squaring the Triangle
Teach budding mathematicians how to square a triangle with an interactive that shows a graphical proof of the Pythagorean Theorem. Pupils alter the lengths of the legs using sliders. Using the inputted lengths, the applet displays the...
Mathed Up!
Pythagoras' Theorem
Use a right method to find a distance. Given a right triangle, class members find the length of one side given the measurement of the other two sides—the missing side may or may not be the hypotenuse. A video reminds the pupils how to...