So f of x plus h minus the y value at x, right? Because this is right here. This is f of x. So minus f of x. All of that over the change in x. So if this is x plus h here, the change in x is x plus h minus x, or this distance right here is just h. The change in x is going to be equal to h. So that's your slope of the secant line between any two points like that. And we said, hey, we could find the slope of the tangent line if we just take the limit of this as it approaches, as h approaches 0.