Question

Find the indicated real nth root(s) of a.

n = 2, a = 400

Root: ?

Answer 1

20 or +-20

Explanation:

They are asking for an nth root. This is generic-speak for square root, third root, fourth root, etc.

Since n is 2, they are talking about 2th root...really 2nd root. But we commonly call that square root.

Square root of 400 is 20. (That's the principal square root because its positive) They asked for real roots, so, technically -20 is also a square root of 400.

20^2 = 400 and

(-20)^2 = 400

So square root of 400 is +- 20.

Or if this is an intro class, then just 20 is probably a good enough answer.