Lesson 9

The Converse

View Student Lesson

Lesson Narrative

This lesson guides students through a proof of the converse of the Pythagorean Theorem. Then students have an opportunity to decide if a triangle with three given side lengths is or is not a right triangle.


Learning Goals

Teacher Facing

  • Determine whether a triangle with given side lengths is a right triangle using the converse of the Pythagorean Theorem.
  • Generalize (orally) that if the side lengths of a triangle satisfy the equation $a^2+b^2=c^2$ then the triangle must be a right triangle.
  • Justify (orally) that a triangle with side lengths 3, 4, and 5 must be a right triangle.

Student Facing

Let’s figure out if a triangle is a right triangle.

Learning Targets

Student Facing

  • I can explain why it is true that if the side lengths of a triangle satisfy the equation $a^2+b^2=c^2$ then it must be a right triangle.
  • If I know the side lengths of a triangle, I can determine if it is a right triangle or not.

CCSS Standards

Addressing

Building Towards

Print Formatted Materials

For access, consult one of our IM Certified Partners.

Additional Resources

Google Slides

For access, consult one of our IM Certified Partners.
PowerPoint Slides

For access, consult one of our IM Certified Partners.