Final answer:
The equation 3/x + 4y = 10 is not a linear function due to the variable x being in the denominator, which is not allowed in linear equations.
Step-by-step explanation:
The equation 3/x + 4y = 10 is not considered a linear function because it has variables in the denominator. In linear equations, like those in the form y = mx + b, there are no denominators involving variables, no exponents on the variables, and the slope is constant throughout the equation. This question implicates several key concepts related to linear equations, such as having a constant slope and the absence of variables in denominators or exponents on variables.