Question

What is the square root of 84?

Answer 1

`+-2sqrt21`

Explanation:

We can break down `sqrt84` into the following:

`sqrt4*sqrt21`

We are able to do this because of the property `sqrt(ab)=sqrta*sqrtb`

Where we can separate the radical into the product of the square root of its factors. `21` and `4` are factors of `84`.

In `sqrt4*sqrt21`, we can simplify to get:

`+-2sqrt21`

*NOTE: The reason we have a`+-`sign is because the square root of `4` can be positive or negative `2`.

`sqrt21` has no perfect squares as factors, so this is the most we can simplify this expression.