What is the square root of 81?

The square root of a number is a value that, when multiplied by itself, gives the original number. In the case of 81, we are looking for a number that, when multiplied by itself, equals 81.

The correct answer, 9, satisfies this condition because 9 multiplied by 9 equals 81 (9 × 9 = 81). Therefore, the square root of 81 is indeed 9.

In contrast, the other numbers—7, 8, and 10—do not meet this requirement. For instance, 7 times 7 equals 49, 8 times 8 equals 64, and 10 times 10 equals 100. None of these products equal 81, which solidifies 9 as the correct square root in this scenario.