Answer:
x^5y
Explanation:
To find the greatest common factor (GCF) of 35x^5y and 42x^5y^3, we need to find the largest expression that divides into both of these polynomials.
The common factor in both of these polynomials is x^5y, which is the GCF. So, the GCF of 35x^5y and 42x^5y^3 is x^5y.