[eli5] Why is imaginary number root -1? Why not root -n, since no number times each other would result in negative number?

Question

[eli5] Why is imaginary number root -1? Why not root -n, since no number times each other would result in negative number?

In: Mathematics

Answer 1

all other numbers are made of ones.

One is the elementary particle that cannot be broken down into any more component parts (except, obviously, it can, but not for these purposes).