# Definition 7. (Great Pyramid Triangle)

Let us have an isosceles triangle with isosceles sides of 356 and a height of 280, and thus a base of 440. Let it be called the Great Pyramid Triangle, because its dimensions are equal to the Great Pyramid of Giza (in Royal Cubits).

*Image 37. The Great Pyramid Triangle*

## Theorem 4. (π in the Great Pyramid)

The number π is hidden in the elements of the Great Pyramid Triangle and its value is (22/7).

#### Proof.

In the Great Pyramid Triangle the base is 440 Royal Cubits, and to have an approximation for π, the base is needed two times and that is compared with the height (Livio, 2002; Warren, 1903). Thus there is

*(2 * 440) / 280 = 880 / 280 = 22 / 7 ≈ 3,142857… ≈ π.*

As we can see, the number π is hidden in the elements of the Great Pyramid Triangle and its value is (22/7).

∎

Notice: The reliability of this theorem improves when the golden ratio is revealed in the same triangle.

## Definition 8. (Kepler Triangle)

A Kepler triangle is a right triangle with the edge lengths in geometric progression. The ratio of the edges of a Kepler triangle is linked to the golden ratio

*φ = (1 + √5) / 2,*

and can be written: 1 : √φ : φ, or approximately 1 : 1.272 : 1.618. (Herz-Fischler, 2000)