Question

Find the greatest common factor of 15x2y3 and -20x³yz.

Answer 1

5x²y

Explanation:

First, factor the two monomials into their prime factors:

15x²y³ = 3 × 5 × x × x × y × y × y

-20x³yz = -1 ×2 × 2 × 5 × x × x × x × y × z

Now pick the common factors (shown in bold below):

15x²y³ = 3 × 5 × x × x × y × y × y

-20x³yz = -1 ×2 × 2 × 5 × x × x × x × y × z

Now multiply together the common factors:

The common factors are: 5, x, x, y

The GCF is 5x²y