WEBVTT

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We're asked to find the
square root of 100.

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Let me write this down bigger.

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So the square root is this
big check-looking thing.

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The square root of 100.

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When you see it like this,
this means the

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positive square root.

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If you're familiar with negative
numbers, you know

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that there's also a negative
square root, but when you just

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see this symbol, that means
the positive square root.

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So let's think about what
this is saying.

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This is asking us find the
number, the positive number,

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that when I multiply that number
by itself, I get 100.

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So what number when I multiply
it by itself do I get 100?

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Well, let's see, if I multiply
9 by itself, that's

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only going to be 81.

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If I multiply 10 by itself,
that is 100.

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So this is equal to-- and let
me write it this way.

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Normally, you could
skip this step.

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But you could write this as
the square root of-- and

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instead of 100, 100 is the same
thing as 10 times 10.

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And then you know, the square
root of something times

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itself, that's just going
to be that something.

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This is just equal to 10.

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So the square root
of 100 is 10.

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Or another way you could write,
I guess, this same

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truth is that 10 squared, which
is equal to 10 times 10,

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is equal to 100.

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