Multiply and simplify: sq rt 7x ((sq rt x) - 7sq rt. 7)

7x (√x - 7√7) Multiply √7x to "√x" and "-7√7" respectively:

√7x*√x - 7√7*√7x

First is to simplify: √7x² - 7√7²x

Extract the squares: x√7 - 7*7√x

Then, we simplify: x√7 - 49√x

After simplifying the equation, I got the answer x√7 - 49√x.