Lincoln is preparing many gifts for a family holiday party. Each gift must either be wrapped with wrapping paper or prepared in a gift bag. Lincoln can wrap a single gift in 6.5 minutes and he can do a giftbag in 2 minutes. Lincoln prepared a total 13 gifts in 57.5 minutes. Write a system of equations that could be used to determine the number of gifts Lincoln wrapped and the number of giftbags he prepared. Define the variables that you use to write the system.