Question

how to find the square root

Answer 1

find the factors
$144=2^4X3^2=(2^2*3)^2=12^2$
therefore $\sqrt{144}=12$
and so for others

Answer 2

1) divide ur no.s into perfect square factors.
2) take the square roots of ur perfect square factors.
3) if ur no. doesn't factor perfectly reduce ur answer into simplest terms.
4) if needed estimate.
5) alternatively reduce ur no. to its lowest common factors as ur first step.