Determine whether the number is a perfect square, a perfect cube, or neither. If the number is a perfect square or a perfect cube, give the roots. The roots may only be rational numbers.

256

555

-64

-4

Rational numbers are described as "numbers that can be written as a fraction, all integers are rational numbers".

256 is a perfect square of 16 or - 16.

555 is neither.

-64 is a perfect cube of - 4

-4 is neither, for the square root of - 4 is 2i, which is an imaginary number.