112 Chords and Arcs

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11-2Chords and Arcs

• Theorems
• 11-4, 11-5, 11-6, 11-7, 11-8
• Vocabulary
• Chord

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Vocabulary

• Chord

• A segment whose endpoints are on a circle.

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Theorem 11-4

• Within a circle or in a congruent circles
• Congruent central angles have congruent chords.
• Congruent chords have congruent arcs.
• Congruent arcs have congruent central angles.

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1 Using Theorem 11-4
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Theorem 11-5

• Within a circle or in a congruent circles
• Chords equidistant from the center are congruent.
• Congruent chords are equidistant from the center.

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2 Using Theorem 11-5
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18
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Theorem 11-6

• In a circle, a diameter that is perpendicular to
  a chord bisects the chord and its arcs.

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Theorem 11-7

• In a circle, a diameter that bisects a chord
  (that is not a diameter) is perpendicular to the
  chord.

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Theorem 11-8

• In a circle, the perpendicular bisector of a
  chord contains the center of the circle.

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3 Using Diameters and Chords
6.8
4
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