What square root equals 21?

What square root equals 21? In other words, what number would you take the square root of to get 21? To solve this problem, we want to find x in the following equation:

√x = 21

To solve the √x = 21 equation, we first raise both sides to the power of 2 to eliminate the square root:

(√x)² = 21²
x = 21²

Then, we calculate 21² to get the following answer:

21² = 21 × 21
21² = 441

√441 = 21

We've provided the equation above to help you understand the underlying concept of solving problems like this. In the future, remember that you can solve all similar problems by simply multiplying the number by itself.

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