Find the Rate of Change: Analyzing y=1-4x Linear Function

The given linear function is $y = 1 - 4x$. This can be rearranged to fit the standard format of a linear equation, $y = mx + b$, as $y = -4x + 1$.

In this form, the slope $m$ is simply the coefficient of $x$. Here, $m = -4$.

The slope of the linear function represents the rate of change of the function with respect to $x$, meaning for every unit increase in $x$, the value of $y$ decreases by 4 units.

Therefore, the rate of change of the function is $m = -4$, which is option 4 among the given choices.

Thus, the solution to the problem is $m = -4$.