So now under the Radical we have √9•2•x⁴•x•y⁴•z. Now we begin to just pull out the perfect parts we take out nine and that turns into a 3 outside of the radical. We can't do anything with two so it stays inside. x⁴ comes out as x² and the single x stays inside. With y⁴ we bring it out and it turns into y² with no y's inside. Lastly x was all alone and it remains that way inside the radical.
Now we just take our perfect outside piece, 3x²y² and combine it with what stayed in our radical √2xz and our final answer is 3x²y²√2xz. Suddenly simplifying these radicals seems like a breeze! All we did was this:
Not that hard huh?