(f - g)(x) = f(x) - g(x)
We have f(x) = 4x - 6 and g(x) = 5x - 5.
(f - g)(x) = (4x - 6) - (5x - 5) = 4x - 6 - 5x - (-5) = -x - 6 + 5 = -x - 1
It's a linear function. The domain of a linear function is the set of all real numbers. Therefore the domain is:
![D=\mathbb{R}](https://img.qammunity.org/2020/formulas/mathematics/middle-school/boffg9646mcc2g25n7flb577fhh95cc0h5.png)