Descartes and the Eiffel Tower
Take the quiz and check your answers!
Descartes’ Coordinates and the Unknown χ
The idea of coordinates I came up with is even used in movie theaters!
If you know the row and seat number, you can easily find your seat!
There were 12 pieces of bread before eating. After eating some, only 3 were left.
To find out how many were eaten, we can use a math sentence with a box □ or the letter χ.
The letter χ is used to show an unknown number.
And the mathematician who first used χ was me—Descartes!
