Two Tangents to a Circle

Discover the relationship between two lines tangent to the same circle. Drag the points B and C around to manipulate the sketch. Turn on and off the buttons to discover the relationships between the distances between the point of intersection and the point of tangency.

1. What appears to be the relationship between the two tangent lines? 2. Turn on the show relationships button and manipulate the sketch. What is the relationship that you are discovering? 3. Write a conjecture to describe this pattern. 4. Turn on the show radii. Identify the quadrilateral that is formed and prove why it is this type of quadrilateral.