What is the distance between - 57 and zero on a number line

The number - 57, is 57 away from 0

From 0 to any number (or from any number to 0) is always the number

For example the substance between 20 and 0 is always 20

or

the distance between - 57 and 0 is always 57

The distance between 0 and - 57 is - 56