Geometry Finding the Area of a Pyramid
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Finding the Area of a Pyramid

 

 A regular pyramid is one with a square base

 and four triangles for sides. 
 These triangles all have 2 sides that are the same length.
 That makes them something called isosceles triangles.
 

 
 We don't know enough math tricks yet
 to show you where the formula 
 for the volume of a pyramid comes from.
 We have to just list it ...
 

 
 Example:
 What is the volume of a pyramid
 with these dimensions ...
 

 
 To find the area of the surface of the pyramid,
 we need one more measurement.
 
 That measurement is called the slant height.
 
 This is the height of the triangles
 that make the sides of the pyramid.
 
 Since the triangle lives on an angle,
 we call the height the slant height.
 

 
 Example:
 Find the area of the surface of the pyramid.
 

 
 The area of the base is:

 8 8 = 64

 (Sometimes we need this area, sometimes we don't)

 
 The 4 sides of the triangles look like this:
 

 
 Each of these triangles are made up of 2 triangles.
 Like this ...
 

 
 There are 2 triangles in each of the 4 sides of the pyramid.
 So the area is ...
 

 Area = 2 triangles per side 4 sides 14

Area = 2 4 14

Area = 112

 
 If the area of the base is added, the total area is:
 
Area = 112 + 64
Area = 176
 

   copyright 2005 Bruce Kirkpatrick

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