Lesson 7
A Proof of the Pythagorean Theorem
Lesson Narrative
In the warm-up of this lesson, students study a diagram they will use to prove the Pythagorean Theorem. In the first activity they prove the Pythagorean Theorem using the diagram. Then they apply the Pythagorean Theorem in the next activity. The final activity before the cool down is an optional look at a transformational proof of the Pythagorean Theorem.
Learning Goals
Teacher Facing
- Calculate an unknown side length of a right triangle using the Pythagorean Theorem, and explain (orally) the reasoning.
- Explain (orally) an area-based algebraic proof of the Pythagorean Theorem.
Student Facing
Let’s prove the Pythagorean Theorem.
Required Materials
Required Preparation
If you choose to do the optional activity, you will need the 5 cut-out shapes from the Making Squares blackline master used in the first lesson of this unit—1 set of 5 for every 2 students. You will also need copies of the A Transformational Proof blackline master—1 copy for every 2 students.
Learning Targets
Student Facing
- I can explain why the Pythagorean Theorem is true.
Print Formatted Materials
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| Student Task Statements | docx | |
| Cumulative Practice Problem Set | docx | |
| Cool Down | Log In | |
| Teacher Guide | Log In | |
| Teacher Presentation Materials | docx | |
| Blackline Masters | zip |