ok easy way is
let's say we want to ifnd if the square root of a nubmer x is between the numbers 3 and 4
what we would do is
3^2=9
4^2=16
and if x is between 9 and 16, then the square root of x is between 3 and 4
so
12
3^2=9
4^2=16
12 is between 9 and 16
therefor squaer root of 12 is between 3&4
