The Geometry of Giza (cont.) By Edward G. Nightingale
So what does the number 45 have to do with a circle? 45 can be seen as 45° degrees of angle within the circle. If we draw a 45° degree angled line from the South West corner to the North East corner of the main circle we can see that the line intersects the South Eastern corners of both the Pyramid of Khafre and the pyramid of Khufu.