Find the GCF of 18a, 20ab,

and bab.

2a^2b

Step-by-step explanation:

(tried my best but can't be sure I remember how to do it correctly)

First, you find the GCF of 18 and 20, which is 2.

18 > 2 * 3 * 3

20 > 2 * 2 * 5

The next part is where I'm a little hesitant. I say there is an 'a' for each number and only one 'b', so we forget about the 'b' and write 'a^2.'