Question

How do you evaluate `sqrt(16-x)` when x = 8?

Answer 1

`2sqrt2`

Explanation:

First substitute 8 for x in the equation
`sqrt(16-8`
Then simplify to get
`sqrt 8`
This can be broken down into surd form to get
`sqrt4. sqrt2`
The square root of 4 is 2, but the square root of 2 is irrational, so can be left in surd form.
This leaves
`2sqrt2`