around 300 BC in Alexandria, first stated his five postulates in his book The Elements that forms the base for all of his later theorems. His first postulates were
             1. To draw a straight line from any point to any other.
             2. To produce a finite straight line continuously in a straight line.
             3. To describe a circle with any center and any distance.
             4. That all right angles are equal to each other.
             5. That, if a straight line falling on two straight lines makes the interior angles on the same side less than two right angles, if produced indefinitely, meets on that side on which are the angles less than the two right angles.
             It has been stated than Euclid was not satisfied with the last postulate, and even tried to derive it from the other four. His first 28 theorems in The Elements are not proven with the last postulate-it is not used until needed. Many other authors have written
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