Zac and Lynn are each traveling on a trip. So far, Zac has traveled 123.75 miles in 2.25 hours. Lynn leaves half an hour after Zac. So far, she has traveled 105 miles in 1.75 hours. Assume Zac and Lynn travel at constant rates. Let x represent the number of hours that have elapsed since Zac started traveling. Let y represent the number of miles traveled. On a piece of paper, write a system of linear equations that represents the distance each of them has traveled since Zac left on his trip. Assume Zac and Lynn continue to travel at the same constant rates and make no stops.