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Topic: Formula for finding squares of numbers
Replies: 1   Last Post: Nov 5, 2008 8:20 AM

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 Butch Adams Posts: 1 From: Alabama Registered: 10/10/08
Formula for finding squares of numbers
Posted: Oct 10, 2008 11:29 AM

Here is a simple process for finding the square of a number. It is something that can be done in one's head rather than multiplying out long-hand.
If you know one square, you can easily derive the square of any other number close to it.
For example, we know the square of 20 is 400. We will solve for 23 squared.
Take the difference between the base of the known number and the base of the number in question (23-20=3).
Multiply each base number by that difference (3x20=60 and 3x23=69).
Add those two products together (60+69=129).
Add that sum to the known square and you have the answer (400+129=529, which is 23 squared).
This works for any whole or decimal.
I can not find this documented anywhere as a formula or as a process, so I have written down the simple formula.
If it is a new method and is useful, please let me know so that I will know if you have applications for it.
Thank you.

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