Which of the following is a factor of 10xy − 5y + 18x − 9?

1.1 Split 10xy - 5y + 18x - 9
into two 2-term polynomials
- 5y + 10xy and + 18x - 9
This partition did not result in a factorization. We'll try another one:

10xy - 5y and + 18x - 9
This partition looks good

1.2 Pull out from each binomial separately
10xy - 5y = 5y • (2x - 1)
+ 18x - 9 = + 9 • (2x - 1)

1.3 Add up to arrive at the desired factorization
(5y + 9) • (2x - 1)

Factorization found :

(5y + 9) • (2x - 1)