its self because a plane figure is a figure that is flat and has all strait sides.
circle
None. A figure must have more sides than angles.
If none of the sides ever cross each other, there cannot be a closed plane figure.
An octagon.
Polygon
A plane figure with eight sides is an octagon.
A polygon is a plane figure with 3 or more straight sides and angles. A plane figure is a flat enclosed figure made of straight lines, curved lines, or both.
A quadrilateral is a closed plane figure with four straight sides.
If they are straight sides, then a polygon. Otherwise, simply "a closed plane figure with 3 or more sides".
its self because a plane figure is a figure that is flat and has all strait sides.
An 8-sided plane figure is an octagon.
circle
A polygon is a plane figure which comprises one area bounded by three or more straight line segments. A general plane figure can have curved boundaries or sides that cross each other.
No plane figure has four vertices unless it has four sides.
hendecagon
None. A figure must have more sides than angles.