Do you mean 4 * sqrt(7 * 7 * 7) ?
If that is what you mean, it can be broken apart like this 4 * sqrt(7 * 7) * sqrt(7)
You can always do something like that. The square root of 7*7 is 7
Try it with your calculator. Put in √(7 * 7)= you should get 7.
So the answer is 4 * 7 * sqrt(7) = 28 * sqrt(7)