Answer: Hello mate!
We have the equation 13 + 52 and we want to write this as the product of their GCF and another sum.
The GCF between 52 and 13 can be obtained in the next form:
52/13 = 4, then 52 = 13*4
then 13 is a factor of 52, and 13 is the GCF between 13 and 52.
our equation can be written as:
13 + 52 = 13 + 13*4 = 13*(1 + 4)
there you have the equation written as the product between the GCF between 13 and 52 and another sum.