SOLUTION: how shall i find the square root of 169 without using calculator?? please describe briefly..

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Question 8481: how shall i find the square root of 169 without using calculator?? please describe briefly..
Found 2 solutions by bonster, arunpaul:
Answer by bonster(299) About Me  (Show Source):
You can put this solution on YOUR website!
if you don't know it, think of the squared numbers that you already know and use them as markers...

for example, you might already know that 12%5E2=144 and you might already know that 15%5E2=225. if so, you know that 169 would be between these numbers. so it would either be 13 or 14

Look at the ending...169 ends with a 9.
if we multiply by 4*4, the ending number will be 6 AND we also know that when we multiply even numbers, the ending number will NEVER end with an odd number like 9.

We know that when we multiply 3*3, it ends in 9.
Then you know that 13*13 would be a good match.
13%5E2=169

You can try to memorize some or just take an educated guess when playing with numbers.

Answer by arunpaul(104) About Me  (Show Source):
You can put this solution on YOUR website!
find out the factors of 169 like
169 = 13*13
so the squrw root = 13
(Ans)other wise u have to follow the method of square root by division method
1|169|13
1|1 |
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23|069|
| 69|
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