Which function has an inverse that is also a function? g(x) = 2x – 3 k(x) = –9x2 f(x) = |x + 2| w(x) = –20

Acable company claims that the average household pays $78 a month for a basic cable plan, but it could differ by as much as $20. write an absolute value inequality to determine the range of basic cable plan costs with this cable company. a. |x − 78| ≥ 20 b. |x − 20| ≥ 78 c. |x − 20| ≤ 78 d. |x − 78| ≤ 20