# Square root of 81

### Square Root Calculator

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#### Square root result:

Sqrt(81). Find the square root of 81 or any other real number, positive or negative. Here are the answers to questions like: Square root of 81 or what is the square root of 81?

## What is square root? Definition of square root

A square root of a number 'x' is a number y such that y2 = x, in other words, a number y whose square is y. For example, 9 is the square root of 81 because 92 = 9•9 = 81, -9 is square root of 81 because (-9)2 = (-9)•(-9) = 81. When writing math, people often use sqrt(x) to mean the square root of x. Read more about square root here: Square Root - Wikipedia and here: Square Root - Wolfram

## Square Symbol?

Here is the square root symbol. It is is denoted by √, known as the radical sign or radix. ### Square root of values around 81

NumberSqrt
The square root of 80.6 is 8.978
The square root of 80.7 is 8.983
The square root of 80.8 is 8.989
The square root of 80.9 is 8.994
The square root of 81 is 9.000
The square root of 81.1 is 9.006
The square root of 81.2 is 9.011
The square root of 81.3 is 9.017
The square root of 81.4 is 9.022
The square root of 81.5 is 9.028