I don’t understand, can someone please help.

When only separate discreet points are graphed it is called?

Suppose you are an avid reader and are looking to save money on the cost of books instead of paying about $20 for each book, you decide to look into purchasing a kindle for $120 you can purchase e-books for about $5 each 1. find the slope-intercept equation for the cost of the hard copy of books using x to represent the number of books 2. find the slope-intercept equation for the cost of the kindle with cost of e-books using x to represent the number of books

Mia’s gross pay is 2953 her deductions total 724.15 what percent if her gross pay is take-home pay