7.3 ~ SA

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7.3 SA Vol of Pyramids
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Pyramids
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Pyramids
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More Pyramids!
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All about Pyramids

• Pyramid
• A polyhedron consisting of a polygon base and
  triangular faces that all meet at a single point
  called the vertex

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All about Pyramids

• Pyramid
• Altitude of the pyramid is the perpendicular
  distance from the vertex of the pyramid to the
  base
• Slant height is the distance from the vertex of
  the pyramid to an edge of the base (the height of
  the triangles)

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What if I dont know a measurement?

• Sometimes you may have to go back to the
  Pythagorean Theorem

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All about Pyramids

• Pyramid
• Pyramids are named by the shape of their base
• Slanted pyramids are oblique and straight
  pyramids are right

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Right or Oblique

• For volume, it doesnt matter!

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Surface Area

• Surface area
• Find the area of each part of the figure (the
  base and each triangle)
• Add the areas together

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NETS
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Surface Area

• SA L B
• L lateral area (area of the triangles)
• B area of the base (whatever it is)

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Surface Area

• You may want to use this formula
• SA ½ lp B
• where l is the slant height
• and p is the perimeter of the base
• What does B stand for?

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Volume

• Volume
• Find the area of the base
• Multiply it by the height of the pyramid
• Divide by 3 (or multiply by 1/3)