square
120
Pentagon A+
It is a regular 10 sided decagon
A square.
Square, or a rectangle. * * * * * Since it is a REGULAR polygon, it cannot be a rectangle. So the only answer is a square.
If it is a regular polygon then it will have 360/12 equals 30 sides
The sum of all exterior angles of a polygon is 360 degrees. In a regular polygon, all of the exterior angle are equal, so there must be 360/72=5 sides of the polygon, which makes it a pentagon.
With any regular polygon it is 180 minus interior angle times number of sides equals 360 degrees
A nine sided shape that is called a regular nonagon.
If it is a regular polygon with each interior angle of 120 degrees then it is an hexagon which will have 0.5((6^2)-3*6) equals 9 diagonals
The regular polygon whose exterior angle measure is 12 degrees, has 30 sides (360/12, since the exterior angles on any polygon always add up to 360 degrees).