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Square Root of 64

Date: 6/20/96 at 15:53:11
From: Anonymous
Subject: Square root of 64

I would like to know the square root of 64. We just started to learn 
square roots, and my teacher did not explain very well. 


Date: 6/21/96 at 11:36:41
From: Doctor Beth
Subject: Re: Square root of 64

A square root of a number is another number, that when you multiply it 
by itself, gives you the first number.  

I know the last sentence sounds a bit confusing, so I'll give you a 
few examples and then it will make sense.  

If I want to know the square root of 4, I ask myself "what multiplied 
by itself gives me 4?"  Then I check, and say 2 x 2 = 4, so the square 
root of 4 is 2.

I can do this with any number I please, but only a few give nice 
integer answers.  Here's another example:  to find the square root of 
16, I ask myself (I talk to myself a lot) "what multiplied by itself 
gives me 16?"  I know it's not 3 (since 3 x 3 = 9) and then I check 4, 
and know I've found that the square root of 16 is 4 since 4 x 4 = 16.  
Now I think that you can figure out the square root of 64!

Now, if you haven't learned about negative numbers yet, you can ignore 
this whole paragraph!  (Don't worry, you'll learn about this stuff 
eventually.) I would be leaving something out if I didn't tell you 
that all positive numbers have two square roots, a positive one and a 
negative one.  This is because a negative times a negative is a 
positive, so (-2) x (-2) = 4, so another square root of 4 is (-2).  In 
the other example from the first paragraph, you can guess what the 
other square root of 16 would be - it's (-4).

-Doctor Beth,  The Math Forum
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Associated Topics:
Middle School Negative Numbers
Middle School Square Roots

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