Write a system of equations to describe the situation below, solve using substitution, and fill in the blanks.


A couple of friends decide to race each other. Valentina can run 7 meters per second, whereas Felipe can run 8 meters per second. Because she is slower, Valentina also gets a head start of 4 meters. Shortly after they start running, Felipe will catch up to Valentina. How long will that take? How far will Felipe have to run?


It will take ____seconds for Felipe to run ____meters and catch up to Valentina.