Answer:
4(4x + 7)
Explanation:
To answer this question you need to understand what GCF is
GCF is Greatest Common Factor
GCF is the highest number that divides exactly into two or more numbers.
The expression is 16x + 28
The highest number that can divide 16 and 28 is 4
Dividing 16x + 28 gives => 16x/4 + 28/4 => 4x + 7
So the factored expression is
4(4x + 7)