Interior Angles of Triangles

This activity will help you meet these educational goals:

• Mathematical PracticesYou will make sense of problems and solve them and reason abstractly and quantitatively.
• 21st Century SkillsYou will use critical-thinking and problem-solving skills.

Directions

Read the instructions for this self-checked activity.Type in your response to each question, and check your answers.At the end of the activity, write a brief evaluation of your work.

Activity

You will use the GeoGebra geometry tool to study the interior angles of triangles.Go tointerior angles of triangles,

(copy and paste in browser)

http://contentstore.ple.platoweb.com/content/GeoGebra.v5.0/A2.6_Interior_Angles_of_Triangles.html

and complete each step below.If you need help, follow theseinstructionsfor using GeoGebra.

Question 1

Record the measures of the interior angles ofABC(,, and), and find their sum.

Question 2

Move verticesA,B, andCto create a triangle of your choice.Record the measures of the interior angles,, andfor three different triangles.Then find the sum of the angle measures for each triangle.

Question 3

How does the sum of the interior angles change as you move the vertices ofABCto create a triangle of your choice?