### Euclid's Postulates

1. A straight line segment can be drawn joining any two points.

2. Any straight line segment can be extended indefinitely in a straight line.

3. Given any straight lines segment, a circle can be drawn having the segment as radius
and one endpoint as center.

4. All Right Angles are congruent.

5. If two lines are drawn which intersect a third in such a way that the sum of the inner
angles on one side is less than two
Right Angles, then the two lines inevitably must
intersect each other on that side if extended far enough. This postulate is equivalent to what is
known as the
Parallel Postulate.

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