Sqrt(125 x^8 y^9)
For sqrt 125 we need to break it down to a perfect square * a not perfect square.
125 = 25 * 5 = 5sqrt5
For Sqrt x^8, since the index is two (because we're doing a square root), divide the power 8 by 2 and you get x^4.
For sqrt y^9, 9 is not divisible by 2 but can do y^8*y. We'll then have
y^4sqrt y.
Putting it all back together:
5x^4y^4 sqrt(5y)
