Do you know what the Pythagorean Theorem is ? If you don't know then keep on reading. The Pythagorean Theorem is a to the 2nd + b to the 2nd = c to the 2nd. For example, if you had a triangle and you know 2 sides of the triangle, you know that c is always the biggest number. So if you had two sides of the triangle, a and b, you would multiply them by themselves and then add to figure out what c is. It doesn't matter what number is a or b but it does matter for c. C always has to be the longest side. 
  

     Have you ever seen exponents before? If so, when ? What do you know about exponents? I know that exponents mean to multiply. So if you had 5 to the 2nd power, you would do 5 x 5  which equals 25. Lots of people misunderstand and they would multiply 5 x 2 and get ten. That's how you would get it wrong. Exponents means to multiply the number times itself how many times it says. If it was 2 with a little 6 by it, you would multiply 2 x 2 x 2 x 2 x 2 x 2. Not just 2 x 6.
    You would multiply 2 x 2 and get 4 and drop all the other twos.
4 x 2 x 2 x 2 x 2.

      Have you ever wondered why a square root is called 'square root' ? Do you know what a square root is ? If you don't, then keep on reading to learn an answer. A square root is if you divide by something and get the answer that you divided with. For example, if I had the number 64. Obviously, I can multiply 32 x 2 but those numbers aren't the same. The number it could be is 8 because 8 x 8 = 64. Lets try another one. If I had the number 49, the answer would be seven because 7 x 7 = 49. There are man different square roots. Here is just a list of some : 
1 x 1 = 1
2 x 2 = 4 
3 x 3 = 9 
4 x 4 = 16
5 x 5 = 25
These are just some but there are many! This is what square roots are.