Friday 27 January 2017

Faces, edges and vertices


Different shapes have different numbers of faces, edges and vertices. 
Is there are relationship between these numbers? 
If you knew the number of faces and edges could you work out the number of vertices? 
To help your investigation have a look at some real shapes and some online here and here.

11 comments:

  1. Ruqayya and Javan 6 Red12:03 pm, January 27, 2017

    We found out if you add the number of faces and vertices and then take away 2 it equals the number of edges.
    That is a quick way to find out the edges.

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  2. The number of faces added by the number of vertices subtract 2 equals the number of edges.

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  3. You could also do vertices-2 plus NO. of faces. I've also observed that you all the numbers are in the 2 x tables

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  4. If you add the number of faces and the vertices and take away 2 this will happen 6+8=14-2=12. If we do one of these lessons again try find clues to solve the relationship between faces and vertices.

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  5. The rule is faces added by the number of vecities ( corners ) then subtract 2 equals the number of edges

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  6. Lara,Siham and Jenniel 6Red12:19 pm, January 27, 2017

    Number of faces + corners of shapes - 2 = edges
    Cube:
    Number of faces =6
    Corners=8
    Edges=12
    8+6=14-2=12(edges)
    Tetrahedron:
    Number of faces=4
    Corners=4
    Edges=6
    4+4=8-2=6(edges)

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  7. A pyramid is a polyhedron for which the base is a polygon and all lateral faces are triangles. In this lesson, we'll only concern ourselves with pyramids whose lateral faces are congruent — that is, they're the same size and shape.

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  8. .A face is a flat surface
    .An edge is where to face meet.
    . A vertex is a corner where edges meet.
    The plural is vertices.
    Here are most common 3D shape

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  9. Another way to find NO. of edges is vertices plus faces-2.

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  10. cube has 6 faces 8 vertice 12 edgess all these numbers are in the 2 timestabel i tell u how i know
    you do 6+8=14-2=12

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  11. A vertex (plural: vertices) is a point where two or more lines meet.
    It is a Corner.
    This tetrahedron has 4 vertices.
    And this pentagon has 5 vertic

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