Final answer:
The domain of the function y = 3x - 4 is all real numbers.
Step-by-step explanation:
The domain of a function is the set of all possible input values (x-values) that the function can accept. In this case, the function is a linear equation y = 3x - 4. Since this is a linear equation, it can accept any real number as an input value. Therefore, the domain is all real numbers.