Final answer:
The polynomial 12x + 28 is factored by finding the greatest common factor, which is 4, resulting in the factored form 4(3x + 7).
Step-by-step explanation:
The student has asked to factor the polynomial expression 12x + 28. To factor this expression, we look for the greatest common factor (GCF) that can be divided evenly into both terms. The GCF of 12x and 28 is 4 because both numbers are divisible by 4, and there is no larger number that can divide both terms. Therefore, we factor out the 4 to get:
4(3x + 7)
So, the factored form of the polynomial 12x + 28 is 4(3x + 7).