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What's the Square Root of 75?

```Date: 08/18/2002 at 00:03:18
From: Priss Edwards
Subject: Sqrt 75

It's been years since I've been in college and my daughter needs
help. Is the sqrt 75

15* sqrt 5
or
5* sqrt 15,

or what? And why?

Priss

P.S. I've bookmarked this site for my daughter.
```

```
Date: 08/18/2002 at 01:14:48
From: Doctor Paul
Subject: Re: Sqrt 75

Write 75 as a product of primes:

75 = 3*5*5

So sqrt(75) = sqrt(3*5*5)

Whenever you have two of the same number inside the square root, you
can bring one of them outside and remove the other. Thus
sqrt(75) = 5*sqrt(3).

Another example:

sqrt(6048) = sqrt(2*2*2*2*2*3*3*3*7) = 2*2*3*sqrt(2*3*7) =

12*sqrt(42)

I hope this helps.  Please write back if you'd like to talk about
this some more.

- Doctor Paul, The Math Forum
http://mathforum.org/dr.math/
```
Associated Topics:
High School Square & Cube Roots
Middle School Square Roots

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