Education Technology

# Activities

• ##### Subject Area

• Math: Middle Grades Math: The Number System

6-8

45 Minutes

• ##### Device
• TI-Nspire™ CX/CX II
• TI-Nspire™ CX CAS/CX II CAS
• TI-Nspire™ Navigator™
• TI-Nspire™
• TI-Nspire™ CAS
• ##### Software

TI-Nspire™
TI-Nspire™ CAS

3.0

## Comparing Pi's and Roots

#### Activity Overview

This lesson involves manipulating the radius of a circle and the sides of a right triangle in an attempt to set the circumference of the circle equal to the hypotenuse of the right triangle

#### Objectives

• Students will compare the circumference of a circle with the hypotenuse of a right triangle in order to compare the sizes of irrational numbers.
• Students will use measurements, formulas and calculator computations, and formulas and exact calculations to make comparisons.

#### Vocabulary

• rational number
• irrational number
• real number
• decimal approximation
• precision

#### About the Lesson

This lesson involves manipulating the radius of a circle and the sides of a right triangle in an attempt to set the circumference of the circle equal to the hypotenuse of the right triangle
As a result, students will:

• Unwrap the circle alongside the hypotenuse.
• Use measurements to find decimal approximations of lengths in order to compare them.
• Use the circumference formula and the Pythagorean theorem to find decimal approximations of the lengths using a calculator.
• Use the formulas to find exact lengths.