If its a regular 9 sided polygon then the exterior angles are 40 degrees.
It is called Tetracontagon.
It has 40 diagonals.Improved Answer:-Using the formula for diagonals of a polygon: 0.5*(442-132) = 902 diagonals
40 lines.40 lines.40 lines.40 lines.
40
I find the name "30-sided polygon", "40-sided polygon", etc. just fine.
The name of a 40 sided polygon is Tetracontagon.
The sum of the interior angles of a convex polygon with n sides is given by (n-2)x180o. So for a 40 sided polygon n=40; thus (40-2)x180o = 38x180o = 6840o.
Number of sides: 360/40 equals 9 sides
If each exterior angle of a regular polygon measures 40 degrees, the polygon is a nonagon (9-sided polygon).
The sum of the exterior angles of a regular polygon equal 360° .If one such angle measures 40° then the polygon has 360/40 = 9 sides.
tetracontahedron
740 The number of digaonals is given by n(n-3)/2, where n is the number of sides (or vertices) of a polygon: 40(40-3)/2=20*37=740 For a proof, see: http://www.artofproblemsolving.com/Wiki/index.php/Diagonal
If its a regular 9 sided polygon then the exterior angles are 40 degrees.
0.5*(402-120) = 740 diagonals
40 sides
40 sides