2. Circles

3. 10.1 Parts of a Circle
Circle – set of all points _________ from a given point called the _____ of the circle.
equidistant C
center
Symbol: C

4. CHORD: a segment whose ________ are on the circle
endpoints

5. RADIUS: distance from the _____ to a point on the circle
center P

6. DIAMETER: distance ______ the circle through its ______
across P
center
Also known as the longest chord.

7. What is the relationship between the diameter and the radius of a circle?OR
D =
½ D
2 r

8. D = ? 24 32 12
r = ? 16
r = ?
4.5 6
D = ? 12 9

9. Use P to determine whether each statement is true or false.Q R T S

10. SECANT sounds like second
Secant Line
A secant line intersects the circle at exactly TWO points.
SECANT sounds like second

11. TANGENT: a LINE that intersects the circle exactly ONE time

12. Point of Tangency

13. Secant Radius Diameter Chord Tangent
Name the term that best describes the notation.
Secant
Radius
Diameter
Chord
Tangent