SECTION+9.2+TANGENTS+TO++CIRCLES

Ojectives: 1. Define tangents and secants of circles 2. Understand the relationship between tangents and certain radii of circles 3. Understand the geometry of a radius perpendicular to a chord of a circle


 * __DEFINITIONS AND BLUE BOXES!!__**

SECANT- Is a line that intersects the circle at two points. TANGENT- Is a line in the plane of the circle that intersects the circle at exactly one point. POINT OF TANGENCY- Is the one point that the tangent intersects. TANGENT THEOREM- If a line is tangent to a circle, then 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 tangent to the circle. THEOREM- The bisector of a chord passes through the center of the circle.

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