39-12w=7-16w need to slove step by step but how?

If the class was going to get a class pet and 5 picked fish and 7 pick bird and 8 picked rabbits have many students were in the

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

How many 2/5s are in 1 and 1/2 plz someone me right now