1. Three Classical Problems of Antiquity Using only a straightedge and a compass

2. Three Classical Problems of Antiquity (using only straightedge and compass) Delian Problem (Doubling the Cube) Squaring the Circle Trisecting a Given Angle

3. Delian Problem: Delos

4. Delos’ Highest Hill

5. Terrace of the Lions

6. Rene Descartes (1596-1650) Constructible Numbers: a is constructible if and only if there exist two points on a number line a units apart: (a,0) or (0,a). Lemma: If a and b are constructible numbers, then a+b, a-b, ab, a/b are also constructible. Lemma: Square roots are constructible numbers.

7. Pascal’s Triangle