Ch 2: Common Core Math Grade 8 - Geometry: Pythagorean Theorem

About This Chapter

Use the resources in this chapter on the Pythagorean Theorem to get your eighth graders proficient in the Common Core math requirements for geometry. This chapter includes engaging video lessons and practice quizzes to help students master fundamental geometry concepts and skills.

Standard: Explain a proof of the Pythagorean Theorem and its converse. (CCSS.MATH.CONTENT.8.G.B.6)

Standard: Apply the Pythagorean Theorem to determine unknown side lengths in right triangles in real-world and mathematical problems in two and three dimensions. (CCSS.MATH.CONTENT.8.G.B.7)

Standard: Apply the Pythagorean Theorem to find the distance between two points in a coordinate system. (CCSS.MATH.CONTENT.8.G.B.8)

About This Chapter

Students who have reached these Common Core standards will understand the Pythagorean Theorem and its use in finding unknown lengths and distances. The lessons in this chapter help students learn about the following:

  • Definition and uses of the Pythagorean Theorem
  • Converse of the theorem
  • Special cases concerning the theorem
  • Applying the theorem
  • Using the theorem to find distance

You'll know that your eighth graders have mastered this standard when they are able to explain a proof of both the Pythagorean Theorem and its converse, as well as use the theorem to find side lengths in right triangles and the distance between two separate points in a coordinate system.

How to Use These Lessons in Your Classroom

The following suggestions will help you implement these resources into your classroom curriculum in order to meet the Common Core standards.

Hold a Pythagorean Scavenger Hunt

Watch the lessons about the Pythagorean Theorem and its applications. Let students search the classroom for objects that appear to have right angles. Have students measure two of the sides, then use the theorem to find the length of the third side. Measure the side in question and compare it to the value found using the theorem to judge whether or not they have truly located a right triangle.

Create Distance Problems

Have students view the lesson 'Finding Distance with the Pythagorean Theorem.' Building off the examples in the lesson, have students work in small groups to design their own distance problems that can be solved using the Pythagorean Theorem. After they've finished, have groups trade work with one another and attempt to answer each other's questions.

Supplement Instruction With Lesson Videos

Students who are struggling to understand a concept often benefit from having the topic explained in a different way. Show the video lessons in addition to your regular classroom instruction to provide alternative approaches to lesson topics.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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Other Chapters

Other chapters within the Common Core Math Grade 8 - Geometry: Standards course