Question 327880
5√48x²-4x√75+9√300x²

First break down each radical

= 5 √16x²*3  -  4x √25*3  +  9 √100x²*3

Now you can simplify

= 5*4x√3 - 4x*5√3 + 9*10x√3

= 20x√3 - 20x√3 + 90x√3

= 90x√3