AutoCAD Tutorial - Using the POLYGON Command
In AutoCAD the POLYGON command is used to create equal-sided polygons in a drawing. The size of the polygon is specified relative to the size of an imaginary circle. The polygon will either be "inscribed", inside the circle or "circumscribed" about the outside of the circle. It can be confusing, but this video shows you clearly how to draw a polygon to the size and number of sides and rotation that you want.