Here, as much for my convenience as anyone else's, is a list of the theorems that have appeared here, with links. Bézout's theorem The intermediate value theorem Vinogradov's three primes theorem Van der Waerden's theorem The square root of 2 is irrational The binomial theorem The Banach-Tarski paradox Eulerian circuits Bachet's duplication formula Lagrange's theorem…
In reality, you are actually coinciding given two points with the points of your ruler. Then you will say, these points are separated by x unit in length.