Activity Overview
In this activity, students will explore the properties of dilations and the relationships between the original and image figures.
Before the Activity
Install the Cabri Jr. App on the students' graphing calculators using TI Connect™, a TI Connectivity cable and the unit-to-unit link cables
See the attached PDF file for detailed instructions for this activity
Print pages 31 - 40 from the attached PDF file for your class
During the Activity
Distribute the pages to your class.
Follow the Activity procedures:
Construct a slider tool to generate a number in the range of approximately -4.5 to 4.5 units
Draw a small scalene triangle on the left half of the screen and mark a point in the center of the screen
Dilate the triangle
Investigate the relationship between the original triangle (the pre-image) and the new triangle (the image)
Drag a vertex of the pre-image and the center of dilations
Observe what happens to the image
Measure the lengths of corresponding sides, angles, and areas of the pre-image and image
Explore different dilation factors
After the Activity
Students will fill in the Data Collection and Analysis sheet.
Review student results:
As a class, discuss questions that appeared to be more challenging
Re-teach concepts as necessary