Based on the given description above, it is said that the graph is made of the length of the side of a square. By definition, a square has equal sides, and the area of getting the square is A=s^2. Therefore, the function rule for this to find the area for any given side length would be y = x^2. Given the y is the area of the graph and x is the length of the side. Hope this answer helps.
There are 2 ways you can write this.
You can either do /1 or /100

The most used is