Two runners training together. One runner is feeling confident because his average pace is better than the other, so they offer them a head start in a race. Runner A can run a 5.1 minute mile so they gave Runner B, who only has an 6.7 minute mile pace, a 3 minute head start. Write a function, using x and y, that represents situation A above AND explain why your model works for the problem. Write a function, using x and y, that represents situation B above AND explain why your model works for the problem.