Luis and Raul are riding their bicycles to the beach from their respective homes. Luis proposes that they leave their respective homes at the same time and plan to arrive at the beach at the same time. The diagram shows Luis's position at two points during his ride to the beach. Write an equation in slope-intercept form to represent Luis's ride from his house to the beach. If Raul lives 5 miles closer to the beach than Luis, at what speed must Raul ride for the plan to work? If x represents the time in hours since the ride began and y represents the remaining distance from the beach, then the equation

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represents Luis's ride from his house to the beach.