There is another way to directly calculate square roots which is very similar to long division:

The first thing about this method is that numbers are "brought down" 2 at a time instead of 1 as in long division. Think of pairs of digits starting from the decimal point going each way.

√163.28 think of as √1 63. 28

The first "group" is the 1. Find the closest square root, which is 1. Write a 1 above the 1 under the square root.

1

√1 63. 28 Now double what ever is on "top" and put to the side and leave a space for an extra digit.

1

2_ √1 63. 28

1

0 63 1 squared is one, subtract from 1 which is 0. Bring down the next "group" which is 63

Now it will look even more like long division with a twist. Find a number 2_ (twenty something), when multiplied by the last digit will equal or almost equal 63 without going over. Example: 21*1, 22*2, 23*3

23*3 is close but gives us 69, too much, so we have to use 22*2 = 44. Subtract 44 from 63, get the result, and bring down the next group. And put a 2 above the 63 because we did 2**2*****2**

1 2.

22 √1 63. 28

1

0 63

44

19 28 Now once again, double what is on top and leave room for an extra digit

1 2.

22 √1 63. 28

1

0 63

44

24_ 19 28 Now think about two hundred forty something times somethng to get near 1928

Let's try 248*8, 248*8 = 1984, too large, so let's use 247*7=1729. Put 7 on top.

1 2. 7

22 √1 63. 28

1

0 63

44

247 19 28

17 29

254_ 1 99 00 Double what is on top, leave an extra digit and keep going!

1 2. 7 7 8 0 1

22 √1 63. 28 00 00 00 00

1

0 63

44

247 19 28

17 29

2547 1 99 00 2547*7 = 17829

1 78 29

25548 20 71 00 25548*8 = 204384

20 43 84

255560 27 16 255561*1 is too large so use 0

0

2555600 27 16 00 2555601*1 is too large so use 0 again

0

25556001 27 16 00 00 25556001*1= 25556001

25 55 60 01

1 60 39 99

So out to 5 decimal places we have √163.28 ≈ 12.77801