Because the interior angles are not an even fraction of 360o ( they are 140o) and thus they cannot form a circle.
Interior angles of triangles (60), squares (90) and hexagons (120) are and thus these shapes can tile the plane.
Yes
If it's a regular hexagon it will tessellate.
nonagon
Because nonagon means 9 sides
Not a regular nonagon.
Nonagon.
A nonagon has nine sides.
A nonagon.
a nonagon
A nonagon
"nonagon" is not a prefix.
It is a nonagon