# Can instantaneous rate of change be negative?

Most certainly! When the instantaneous rate of change of a function at a given point is negative, it simply means that the function is decreasing at that point. As an example, given a function of the form $y = m x + b$, when m is positive, the function is increasing, but when m is negative, the function is decreasing. For a line, the rate of change at any given point is simply m.