Rationalizing denominations , please help my teacher never even explained

You use math in day-to-day routines when grocery shopping, going to the bank or mall, and while cooking. how do you imagine you will use math in your healthcare career?

Ined this is due tomorrow and i dont know the answer can you find all the exponents

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