page+9.2


 * __9.2__**


 * Objectives**- Define tangents and seconts of circles.
 * Understand the relatonship between tangents and certain radii of circles.
 * Understad the geometry of a radius perpendicular to a chord of a circle.

__**Definitions:**__


 * Secants**- A line that intersects the circle at two points.


 * Tangents**- Line in the plane of the circle that intersects the circle at exactly one point.

__**Theorems**__:
 * Tangent**-If a line is tangent to a circle, the the line is perpendicular to a radius of the circle drawn to the point of tangency.


 * Radius and Chord Theorem**- A radius that is perpendicular to a chord of a circle bisects the chord.


 * Converse of the Tangent Theorem**- If a line is perpendicular to a radius of a circle at its endpoint on the circle, then the line is perpendicular to the circle.


 * Theorem**- The perpendicular bisector of a chord passes through the center of the circle.

Solution:__ (AX)²+8²=10² (AX)²=10²-8² (AX)²=36 AX=6
 * Example -** __Circle P has a radius of 10 in. and PX is 8 in.PR is perpendicular to AB at point X. Find AB.

link to 9.3