To find a square root of a number that doesn’t have a whole number, you have to find the closest square roots with a whole number.
8*8= 64 9*9= 81
The square root of 71 will be between the numbers 8 and 9.
If you find the number between 64 and 81 it will be easier to find the answer.
The middle number for 64 and 81 will be 72.5
Now you know that 71 is closer to 8 rather than 9 and less than 72.5
The answer can not be 8.5 because that is almost the square root of 72.5
Now you have to choose between the numbers 8.1, 8.2, 8.3, or 8.4
We know that the answer can’t be 8.1 or 8.2 because they are too close to the square root of 64.
Now we have 8.3 or 8.4 to choose from. since 8.5 was about 72.5. The answer must be 8.4 because it is closest to 8.5 and 8.5 was a little less then 72.5