# How do you multiply #sqrt(-20) times sqrt(-5) #?

##### 1 Answer

#### Answer:

#### Explanation:

## First, Factor Out #i#

Negative numbers under square roots aren't pretty. Now, we know that

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Then, Multiply the Radicals

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To multiply radicals, simply multiply the numbers inside them, and put a radical over the result, as shown below:

*Note that you can only multiply radicals like this when the radicals are of the same power. If one of your radicals was a cube root instead of a square root, for example, you would not be able to multiply them this way.*

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Lastly, Deal with

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Don't forget our

Recall that

Now, we just tag this on to the result from step 2, and we're done!

Hope that helped :)