1. Monday December 16

2. Test Friday 

3. Analytic Geometry
UNIT QUESTION: What special properties are found with the parts of a circle?
Standard: MM2G1, MM2G2
Today’s Question:
How are central angles different from inscribed angles?
Standard: MM2G3.b

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

5. CHORD:
A segment whose endpoints are on the circle

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

7. Radius
RADIUS:
Distance from the center to point on circle P

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
True: thumbs up False: thumbs down

10. SECANT sounds like second
Secant Line:
intersects the circle at exactly TWO points
SECANT sounds like second

11. a LINE that intersects the circle exactly ONE time
Tangent Line:
a LINE that intersects the circle exactly ONE time
Forms a 90°angle

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

13. Arc Length
A portion of the circumference of the circle – as if you used a ruler to measure the length A B

14. THINGS TO REMEMBER: A circle has 360 degrees
A semicircle has 180 degrees
Vertical Angles are Equal
Linear Pairs are Supplementary

15. Central Angle : vertex is at the center of the circleP C B
APB is a Central Angle

16. Case I: Vertex is AT the centerP C B

17. Semicircle: An Arc that equals 180°
To name: use 3 letters E D
EDF P F

18. Central Angle : vertex is at the center of the circle
Major Arc
Minor Arc
More than 180°
Less than 180°
ACB P AB C B

19. measure of an arc = measure of central angle
96 Q
m AB =
96° B C
m ACB =
264°
m AE
= 2x Find x.
x = 35