The equation of a circle whose center is at (1,2) and radius is 5 is

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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

The equation of line wx is y=2x-5. write an equation of a line perpendicular to line wx in slopeintercept form the contains points (-1,-2)