# Properties of Tangents (CO)

- Author:
- Cara O'Malley, Tim Brzezinski

**Be sure to move points C &/or A around after completing each step below.**There is also a point to change the circle's radius (if you wish). Instructions: 1) Construct radius AE & radius AD. 2) Find the measure of angle CEA & angle ADC. 3) Move point C around. What do you notice about the two angle measures you obtained in the previous step? YOU SHOULD NOW BE ABLE TO COMPLETE THE FIRST CONJECTURE IN YOUR NOTES. 4) Click on the red "Show Segments Tangent to Circle" icon. 5) Measure the lengths CE & CD. What do you notice? 6) Move point C around. What do you notice about the lengths of the 2 tangent segments you obtained in the previous step? YOU SHOULD NOW BE ABLE TO COMPLETE THE SECOND CONJECTURE IN YOUR NOTES.

Activity questions appear above the applet.

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