AutoCad :: Make Rectangle Centered Around Center Point

I used to work with inventor in a class and now lets say i draw a circle of an arbitrary radius/diameter. I mark the center of the circle using the dimcenter command.

I draw a small rectangle around this center mark (this rectangle fits inside of the original circle.)

I want to make each side of the rectangle equally distant from this center point. Since I roughly drew the rectangle around the center point, all sides are not equally distant. How can I do this?

In inventor, I would dimension each side out (dimension from the center point to each side of the rectangle), and double click the dimension and edit the numbers. I would make all the numbers on each side two for example, therefor each side of the rectangle would be two units distance from the center point.