An example of a perfect square is:
1x1, 2x2, 3x3 or it could be written 1², 2², 3².
If you noticed, the intervals in between each perfect square is an odd number.
-You Have to finish your Number Line.
- Tell what you know about these squares :
        
Here is a video about square roots.
Here is a link to a page that helps you with square roots.