10.2: Inscribed Angle Theorem
This activity is intended to supplement Geometry, Chapter 9, Lesson 4.
Problem 1 – Inscribed Angle Theorem
Start the Cabri Jr. application by pressing the APPS key and selecting CabriJr. Open the file INSCRIB1 by pressing
1. Move point
Position 
Measure of 
Measure of 


1  
2  
3  
4 
2. Angles
Open the file INSCRIB2. You are given circle
3. Move point
Position 
Measure of 
Measure of 

1  
2  
3  
4 
4. Make a conjecture about two inscribed angles who intercept the same arc in a circle.
Open the file INSCRIB3. You are given circle
5. In circle
6. In circle
Problem 2 – Extension of the Inscribed Angle Theorem
Open the file INSCRIB4. You are given circle
7. Move point
Position 
Measure of 
Measure of 
Measure of 

1  
2  
3  
4 
8. Make a conjecture: The angle formed by the intersection of
Open the file INSCRIB5. You are given circle
9. Move point \begin{align*}A\end{align*} to 2 different positions and move point \begin{align*}B\end{align*} to 2 different positions and collect the data in the table below.
Position  Measure of \begin{align*}\angle{ACB}\end{align*}  Measure of \begin{align*}\angle{ADB}\end{align*}  Measure of \begin{align*}\angle{ABE}\end{align*} 

1  
2  
3  
4 
10. Make a conjecture: The angle between a chord and the tangent line at one of its intersection points equals ______________ of the central angle intercepted by the chord.