√5m/√5n
so here you have to rationalize it by making the denominator not a root. and to do that the easiest way is to multiply it by itself.
*but when you multiply you multiply it to both numerator and denominator
√5m×√5n÷√5n×√5n
then multiply
√25mn÷√25n^2
√5·5·m·n/√5·5·n·n
then simplify
5√mn/5n
√mn/n
