Factor out the GCF from the given polynomial.

28x-7=_____

In the given polynomial 28x - 7, the greatest common factor (GCF) is 7.

When we factor out 7 from each term, we get:
(7)(4x) - (7)(1) = 28x - 7

Therefore, after factoring out the GCF, the polynomial becomes:

7(4x - 1)