P is a function about X. What is the specific function?

The application problems in junior high school are mainly linear functions or quadratic functions. So if the judgment is not a linear function, it is probably a quadratic function.

Characteristics of linear function: slope k is a constant. K=△y/△x？

It can be seen from the figure that △y/△x =? 8.5-7.5/3- 1 ? = 10-8.5/6-3 = 12- 10/ 10-6 ? =0.5

Is a fixed value. So K=△y/△x =0.5?

So we can know that p is a linear function of x.