Describe how the rate of change and initial value of the linear function are represented in the graph of the function

Look at the following graph of the given equation. determine whether the equation is a function. explain why or why not.

Ivan and jeff buy a package of 8 pens for $4.00. ivan wants 5 of the pens, and jeff wants 3.how much should each student pay?

Solve for n? [tex]z = \frac{3}{4} mn[/tex]