Answer:
x ≠ 4/5, x ≠ 9/4
You can also write it as "all real numbers except 4/5 and 9/4."
Step-by-step explanation:
The denominator of a fraction cannot equal 0. We can write this relation to find what x does NOT equal:
(5x - 4)(4x - 9) ≠ 0
We can use the zero-product property to get two separate equations:
5x - 4 ≠ 0
5x ≠ 4
x ≠ 4/5
4x - 9 ≠ 0
4x ≠ 9
x ≠ 9/4
