Do you mean "how exactly to draw a hexagon?" or do you mean something like "how to write the mathematically precise coordinates of a hexagon?" Do you want the answering person to pick a size (radius) of whatever value they want, or do you want a general answer with a radius r instead of a radius of a particular value?
Here's how to draw one:
Mark where you want the center to be.
Mark where you want one of the vertices to be.
Draw a circle from the center, that intersects the vertex.
Draw a line segment from the center to the vertex.
Using a protractor, mark off 60 degrees, 120, 180, 240, and 300 degrees around the circle.
Those marks, along with the first vertex, are the verteces of the hexagon.
Draw line segements from the original vertex to the 60, 120, 180, 240, and 300 degree marks, then back to the original vertex.
You have drawn a regular hexagon.
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