# Golden ratio in an octagonal building

- Author:
- Thierry Dana-Picard

- Topic:
- Constructions, Geometry, Triangles, Trigonometry

## Golden Ratio in an octagonal synagogue

We use augmented reality to check some proportions in a 19th century synagogue (Rumbach St., Budapest).
The plan can be found on the internet. Students may check some proportions. The trapezes created by the external wall and the internal columns verify the following property: the ratio of the bases of the trapezes are equal to the golden ratio.
Another applet in this book checks the same property for an octagonal medieval castle in Southern Italy.