Lana is driving home from her friend’s house. She is driving at a steady speed, and her distance from her home, in miles, can be represented by the function [math]f(x) = –40x + 15[/math], where [math]x[/math] is her driving time in hours. Find the inverse function [math]f^{–1}(x)[/math] to show when, in hours, Lana will be [math]x[/math] miles from home.
