Final answer:
The equation for the relationship between a square's side length and its perimeter is p = 4s, with a constant slope of 4, because the perimeter is always four times the length of one side.
Step-by-step explanation:
The equation p = 4s describes the relationship between a square's side length s and perimeter p. The slope between each pair of points (s, p) is equal to 4. This is because a square has four equal sides, so the perimeter is four times the side length. In the slope-intercept form of the equation, y = mx + b, the slope m represents the rate of change between the independent and dependent variables. Here, the side length s is the independent variable, and the perimeter p is the dependent variable which changes based on the side length. The slope is found by taking the rise over the run, and for every unit increase in side length, the perimeter increases by four units.