Cones

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Cones

• Geometry
• Mr. Bower
• BowerPower.net

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What is a cone?

• When you spin a right triangle (using one of the
  legs as an axis), you get a cone

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Cones vs. Pyramids

• How are cones and pyramids similar?

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Cones vs. Pyramids

• How are cones and pyramids similar?
• How are cones and pyramids different?

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Parts of a cone
APEX

• The apex is the point at the top of the cone

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Parts of a cone

• The base is the circle at the bottom (or top, if
  youre eating ice cream!) of the cone
• The radius of that circle is called r.

BASE
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Parts of a cone

• The perpendicular distance from the circular base
  to the apex is the height, which we call h.

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Parts of a cone

• The slant height, which we call l, is the
  distance from the apex to a point on the circle.

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Right triangle in a cone

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Cone Lateral Area

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Cone Surface Area

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Cone Volume

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Cone Example

• A cone has a height of 8 cm and a slant height of
  10 cm.
• Find the cones
• Lateral Area
• Surface Area
• Volume

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Cone Example How to start

• A cone has a height of 8 cm and a slant height of
  10 cm.
• Lets start by making sure we know
• h, r, and l.

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Cone Example How to start

• A cone has a height of 8 cm and a slant height of
  10 cm.
• h 8 and l 10
• We need to calculate r.

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Cone Example How to start

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Cone Example How to start

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Cone Example How to start

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Cone Example How to start

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Cone Example How to start

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Cone Example Lateral Area

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Cone Example Lateral Area

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Cone Example Lateral Area

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Cone Example Surface Area

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Cone Example Surface Area

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Cone Example Surface Area

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Cone Example Surface Area

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Cone Example Volume

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Cone Example Volume

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Cone Example Volume

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Cone Example Volume

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Cone Summary

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