Write a system of equations to describe the situation below, solve using substitution, and fill in the blanks. Mrs. Becker, the P. E. teacher, is pairing off students to race against each other. Rafi can run 7 yards per second, and Dale can run 9 yards per second. Mrs. Becker decides to give Rafi a head start of 40 yards since he runs more slowly. Once the students start running, Dale will quickly catch up to Rafi. How far will Dale have to run? How long will that take?

Dale will catch up to Rafi after running
yards in
seconds.