What is the greatest common factor of 4x^2y and 6xy^3?

1. Factor the coefficients into primes: 4 = 2 times 2, and 6 = 2 times 3. 2. Write the variables in expanded form: the first expression has x times x times y, and the second has x times y times y times y. 3. The shared factors are one 2 from the coefficients, one x, and one y, since the first expression only offers a single y. 4. Multiply the common factors together: 2 times x times y gives 2xy. _Source: OpenStax Elementary Algebra (CC BY 4.0), Ch 7 "Factoring", section 7.1 Greatest Common Factor and Factor by Grouping_