The Add Objects Polygon tool inserts a Polygon primitive in the Working-Volume at the location of the 3D Cursor.
Polygon primitives can also be generated with exact dimensions or drawn interactively using the Build > Build Primitives menu.
The Build Primitives Polygon Tab page enables the generation of polygonal (all polygons in the same plane) models by a specified dimension.
Type in the desired Radius, number of Side, and Center point, then press the Make button. Note that the Center is the point in the Working-Volume 3D space that the center of the Polygon is placed.
You can also interactively generate a Polygon primitive by dragging out a bounding box in any of the Working-Volume' TOP, FRONT, or SIDE views. The specified Polygon will fill the space of the bounding box. Note that the Auto checkbox must be checked to interactively draw primitives.