Can anyone give me a simple answer to understand what root squared is and a way I can easily do it if ur stupid at maths

I think you want the definition of square root?

"In mathematics, the square root of a number ' a' is a number "y" such that

"y" times "y" equals 'a' "

So that the square root of 36 = 6.

Think of a square that is 8 by 8. The area of this square is 8*8 = 64

Put another way, 8 squared = 8^2 = 8*8 = 64

The square root will undo what squaring does. The square root of 64 is 8. We're just going in reverse. Your teacher will use "inverse" as a fancy math way of saying "opposite" or "reverse"