13­2 Arcs and Chords.notebook
April 02, 2013
13­2 Arcs and Chords
DO NOW
State the length of the radius of a circle with the given diameter.
3. 6in.
5. 3ft.
7. √24 cm.
State the length of the diameter of a circle with the given radius.
9. 12ft.
11. 6.2mm.
13. In circle O a diameter AB = 3x + 13, and
AO = 2x + 5 (radius). Find the length of the radius and diameter Apr 29­6:59 AM
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13­2 Arcs and Chords.notebook
April 02, 2013
13­2 Arcs and Chords
Congruent central angles have congruent chords. D
If <AOB ≅<COD then AB≅ CD
A
O
C
If AB≅ CD then <AOB ≅<COD B
Congruent arcs have congruent chords. (
(
If AB ≅CD then AB≅ CD
(
(
If AB ≅CD then AB≅ CD
Apr 29­6:59 AM
2
13­2 Arcs and Chords.notebook
April 02, 2013
If two chords are parallel then the intercepted arcs between them are congruent.
D
(
(
A
If AB ll DC, then AD ≅ BC
O
C
B
Apr 29­7:39 AM
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13­2 Arcs and Chords.notebook
April 02, 2013
If two chords are congruent , then they are equidistant from the center.
If AB≅CD then OE≅OF
D
A
apothem
F
If OE≅OF then AB≅CD
O
E
C
B
Apr 29­7:50 AM
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13­2 Arcs and Chords.notebook
April 02, 2013
A diameter perpendicular to a chord bisects the chord and its arcs.
Τ
D
A
If AOC DB then?
E
O
C
B
Apr 29­7:50 AM
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13­2 Arcs and Chords.notebook
April 02, 2013
A
15. If AB = 48 and OC = 7, find OB.
D
C
O
E
B
Apr 29­1:23 PM
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13­2 Arcs and Chords.notebook
April 02, 2013
19. If AB = 20, and OB = 15, find OC.
A
D
C
O
E
B
Apr 29­10:53 AM
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13­2 Arcs and Chords.notebook
April 02, 2013
In circle O, AOC and BOD are
diameters. Prove that AB ll CD.
Statements
Reasons
C
B
O
D
A
Apr 2­2:47 PM
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13­2 Arcs and Chords.notebook
April 02, 2013
Homework
pg 551­552
# 14­20 evens & 26
Apr 29­1:40 PM
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13­2 Arcs and Chords.notebook
April 02, 2013
Apr 2­1:49 PM
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