Question

What's the opposite of -21? :D

Answer 1

21

Explanation:

Opposite number or additive inverse of any number (n) is a number which, if added to n, results in 0, the identity element of addition. The opposite number for n is written as −n.

Answer 2

The answer is:

21

Mathematical key for opposite numbers:

The opposite of a negative number is its positive number.

The opposite of a positive number is its negative number.

Therefore, the opposite of -21 is 21.