remember its a regular 'n' sided polygon..
2007-03-29 20:43:04 · 5 answers · asked by swapnil marothi 1 in Science & Mathematics ➔ Mathematics
The answer to this is more complex than I thought. Here is a link that goes over this in excruciating detail.
http://www.cs.uwaterloo.ca/journals/JIS/sommars/newtriangle.html
Here is a partial list.
Sides Triangles
3.............1
4.............8
5...........35
6.........110
etc.
2007-03-30 08:52:17 · answer #1 · answered by Northstar 7 · 0⤊ 0⤋
I think that for an n sided polygon the answer is n*(n - 3) triangles round the edge with other shapes in the middle. For some reason this doesn't work for n = 3, i.e. a triangle itself, unless you say there are none round the edge and one in the middle. It is possible that some of the shapes in the middle could also be triangles but I haven't checked this.
Edit. The formula in the answer below for n = 6 gives 20. However, if you draw it you will see that there are 18 triangles round the outside and 6 quadrilaterals in the middle.
2007-03-29 22:12:19 · answer #2 · answered by mathsmanretired 7 · 0⤊ 1⤋
the no. of triangles formed in a 'n' sided polygon is equal to the no of sides +2 i.e. in a polygon with 'n' sides the no of triangles will be n+2
2007-03-29 21:22:31 · answer #3 · answered by harry 1 · 0⤊ 1⤋
18
2007-03-29 20:51:09 · answer #4 · answered by nordinanoka 2 · 0⤊ 1⤋
no of triangles= nC3= n(n-1)(n-2)/6
2007-03-29 22:47:12 · answer #5 · answered by tarundeep300 3 · 0⤊ 1⤋