Lesson Objective

Students will master the application of the Pythagorean Theorem to solve for missing side lengths, verify right triangles using the converse, and solve multi-step real-world problems.

Students will also approximate square roots to determine distances on a coordinate plane and in scaled drawings.

How can we estimate the value of a non-perfect square root without a calculator?

How does the Pythagorean Theorem allow us to find the distance between points without a specific formula?

How do changes in scale affect the calculation of real-world distances?

Hypotenuse, Legs, Radical, Irrational Approximation, Converse of the Pythagorean Theorem, Perimeter, Area

8.NS.A.2: Use rational approximations of irrational numbers.

8.G.B.7: Apply the Pythagorean Theorem to determine unknown side lengths.

8.G.B.8: Apply the Pythagorean Theorem to find the distance between two points.

DOK Level 3 (Strategic Thinking). This lesson is a cumulative review.

Students often confuse the legs (a and b) with the hypotenuse (c).

Some may incorrectly assume the distance formula is a separate entity rather than an application of PT.

Students may also struggle with the order of operations when calculating.

Scaffolding: Provide a "Perfect Square Reference Sheet"

Challenge students with 3D applications (finding the diagonal of a rectangular prism)

Use graph paper for all distance problems

Exit Ticket

Performance Task