Education Technology

# Activities

• ##### Subject Area

• Math: Algebra I: Linear Functions

6-8

45 Minutes

• ##### Device
• TI-73 Explorer™
• ##### Other Materials
Please see the attached .pdf for more details.

## Comparing Rate of Change for Skate Rental

#### Activity Overview

Students will compare charges from two skate rental shops and, using data from their lists & graphs, determine the conditions required for one shop to be less expensive than the other.

#### Before the Activity

Make sure all functions are cleared or turned off. Set Window as follows: 0 < x < 8, - 2 < y < 18.

#### During the Activity

Monitor students as they enter their information into the lists and as they set up the Stats Plots. Use Plot 1 to graph Revolution Rentals data, and use Plot 2 to graph the data for Sk8ers Ruul. Be sure to have students select a different mark for each of the two line graphs. As students begin answering the questions, they may say that there will be two points at which the rental charges are the same, since the line graphs intersect at two places. Help them to compare the line graphs with the data represented in the lists to understand that although the line graphs do intersect twice, only one of those intersections occurs at an hourly increment.

#### After the Activity

Review student results:

• As a class, discuss questions that appeared to be more challenging
• Re-teach concepts as necessary