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•  Prism patterns  •  •  •  •  •  •  •••••••••••••









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                                                m Copy this table.
                                                   Complete it for the six prisms shown at the top of these two pages.
                                                   Start with a  and finish with f.
                                                   Handle real shapes to help you,  if you want.
                                                                                           •  Draw a table showing your answers.
                                                   ---- _ _!~~--- ----- ----- ----          How many edges does each end face of a  prism hove if it has:
                                                   ~----~~e_C}_~'!~~~~---- ----- ---- -----  A heptagon is   a  42 vertices   b  18 faces?
                                                                         a closed shape
                                                    --- __ !!_~'!!~--- ----- ----- ----  wlth7straightsides.
                                                    _!_  ---~'-"-'!!.~°!___ _.!_ --  -   /   CHALLENGE                     '
                                                    ___ _ __!:!~ondl  _  _ _____________ _   •  For each prism in your tables from lfij and (]].compare the number
                                                                                           of edges with the number of faces and vertices added together.
                                                        octago11a/
                                                                                          •  Try to spot a  pattern and explain it in words.
                                                                                          •  Try to write the pattern as a  formula.
                                                [E'.I   Explain any patterns in your results.
                                                m
        [I]

         letter      prism name         number of      number of     number of              letter      prism name         number of      number of     number of
                                           faces        vertices       edges                                                 faces         vertices       edges
           d          triangular             5              6             q                   a         nonagonal              11            18             27
           b         rectangular             6              8            12                   b         decagonal              12            20             30

           f         pentagonal              7             10            15                   c        undecagonal             13            22             33
           a          hexagonal              8             12            18                   d        duodecagonal            15            24             36
           c         heptagonal              q             14            21                   e         icosagonal             22            40             60

           e          octagonal             10             16            24


                                                                                           a  21       b  16
        The number of faces, plus the number of vertices, is 2 more than the               Challenge
        number of edges. The number of vertices increases by 2 each time. The
        number of edges increases by 3.                                                    The number of faces, plus the number of vertices is 2 more than the
                                                                                           number of edges.
                                                                                           F+V=E+2
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