1. Construct segment DA
2. Create an isosceles triangle with base angles twice the measure of the top angle (72 degrees vs. 36 degrees)
3. Create angle bisector for 72 degree angle.
4. The line intersected is in the ratio of the Golden Ratio.
5. Each additional triangle created can be further divided into the Golden Ratio.
If Geometers Sketchpad available: GSP Golden Ratio