Even and Odd Roots of Negatives Values...

[johnkim4]

Why is it possible to take an odd root of a negative number, but not possible to take an even root of a negative?

[jnelson0612]

John, I can cube a -3 and reach a result of -27. Thus, I can take a cube (or third) root of -27 and get -3. That is mathematically possible.

The GMAT will never have you take an even root of a negative number because such a number is impossible to attain. For example, can you think of any number that when it is squared will give you -16? No! To get -16 I must have an odd and an even number multiplied together. There is no one number I can square that will give me this result.

I hope this helps!