You can put this solution on YOUR website!
To find the domain, you must make sure the denominator does NOT equal zero. In this case, make sure that 4-9x does NOT equal zero.
To solve this, solve
4-9x=0 and the domain will be all values of x EXCEPT this value!
Domain is all values of x EXCEPT 4/9.
For additional explanation, please see my website by clicking on my tutor name "rapaljer" anywhere in algebra.com. Then look for MATH IN LIVING COLOR, which is about the third link on my homepage. Choose College Algebra, then Chapter 2, the section called "Functions, Domain, and Range".