Thales and the Pyramid
Take the quiz and check your answers!
Right Triangle and Pyramid
One day, while I was traveling in Egypt, I saw massive pyramids scattered all around, even back then. At that time, no one knew the exact how tall they were. As the sun began to set and the shadows grew longer, I placed my staff upright in the ground. At that moment, the shadow of my staff became exactly the same length as the staff itself.
Look closely. The right triangle formed by the pyramid and its shadow is similar to the right triangle formed by the staff and its shadow. Since the shadow of the staff is equal to its height, the same applies to the pyramid: the length of its shadow equals its height.
Quiz
For example, if my height is 150 cm, and my shadow is also 150 cm, and the shadow of a building is 200 meters long, how tall is the building?