Radicals

Radicals are the inverse operation of exponents.  The most common one is the square root, which asks you to find what number multiplies by itself in order to get the number under the radical.  Sometimes there won't be a clear answer, and in that case you will have to factor the number down into numbers that are squares and numbers that aren't.  Then you can pull the ones that are out by taking their square root and leave the numbers that aren't inside.

Here's a video explanation.

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Part 2: Examples

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Part 3: Estimating the value of a square root.

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