Arcs and Central Angles

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Arcs and Central Angles

• Geometry
• Mr. Bower
• BowerPower.net

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Central Angles

• The vertex is the center of the circle
• The sides are radii of the circle

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Central Angles

• ? XCY is a central angle
• YOU ?Name two more central angles

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Central Angles

• What is the sum of the red, blue, and green
  central ?s?

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Arcs

• The measure of measure of its an
  arc central angle
• m?XCY 80
• m XY 80

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Arcs

• The measure of measure of its an
  arc central angle
• m?ZCY ???
• m ZY ???

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Arcs

• The measure of measure of its an
  arc central angle
• m?ZCX ???
• m ZX ???

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Arcs

• What is the sum of the red, blue, and green arcs?

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Minor Arcs

• Minor arcs are lt 180
• When you see exactly two letters, this is a minor
  arc
• m ZX 160

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Major Arcs

• Major arcs are gt 180
• When you see three letters, follow the path of
  the letters it may be a major arc
• m ZYX 200

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Semicircle

• A semicircle is an arc 180
• Do you see that the central angles are also 180?
• m AMB 180
• m ANB 180

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