Answer:
the correct solution is letter A.
Explanation:
We have the following expression:
6sqrt(7) - 5x*sqrt(7) - x*sqrt(7)
Grouping the expression, we have:
=sqrt(7)*[6 - 5x - x]
=sqrt(7)*[6 - 6x]
= 6*sqrt(7)- 6x*sqrt(7)
So the correct solution is letter A.