Answer:

Step-by-step explanation:
Okay, lets break this problem down. Instead of solving the expression given, we are rather simplifying it as if we would fractions. A GCF is used to separate the largest number that can be multiplied into another number. For example,
Say if we had the numbers:
21 & 28
We are looking for the GCF, or Greatest Common Factor.
A factor is a number multiplied by another number to achieve the same outcome, for instance, take 4. The factors are 2 and 2, along with 4 and 1.
Now back to the example. 21 and 28 have what number in common? 7 If we take the number 7 out of 21 and 28 we get this:

Basically, we are looking at the same problem, but in simpler terms.
Now, looking at the problem originally given, we have:

Now remember, A GCF always is the same number. We can't use unlike numbers for a GCF . The number for both parts of the expression must be the same.
I hope that this provided you with some clarification and I would be happy to help you again in the future! Have a nice day!