In the diagram below, P is a point inside square ABCD. Find x.
The diagonal of a square is its side times the square root of two.
Well, it works the other way, also.
The side is the diagonal divided by the square root of two.
In this square, we see that the diagonal is two.
So, two divided by the square root of two, is the side.
–——— = sqrt(2)
x = sqrt(2) = approx 1.414