please look at the photo attached, its really confusing me so even if you dont know the answer can you atleast give me tips on how to do it? note: the rectangle is 4cmx11.5cm, scaled up it is 8mx23m

Which graph represents an even function?

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

Ineed to know the ordered pairs for this equation i need the answer quick because it’s a timed test