Simplifying radicals is an extremely important skill for your child to master. Once they do, you will be amazed at the confidence with which they will approach just about any algebra question that can be given to them. But there are a few things they do need to know, before continuing.
Ensure they know:
According to the Rules of Radicals.. 

The square root of 9 is 3, and the square root of 25 is 5 
Know the Perfect Squares 
According to the Rules of Radicals... 

Here knowing the perfect square 9 and seeing that 9 is a product of 18 is simply a skill your child will have to develop through practice. This is why it is so important to know the perfect squares. They should also be able to spot 49 as a perfect square of 7 (7x7=49) 
Know the Perfect Squares 

According to the Rules of Radicals... 

We cannot 'tidy' this answer up any more. 
As you can see  all there is to simplifying radicals is the skill to observe perfect squares when they exist, and knowing the rules of radicals.
But this is one skill that requires lots and lots of practice. If your child does practice, it will soon be second nature!
If you are done with simplifying radicals head to our radical numbers section , our Basic Algebra Section, or explore all that Printable Math Worksheets has to offer.
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