A student has some $1 and $5 bills in his wallet. he has a total of 1919 bills that are worth $5959. how many of each type of bill does he hav

X = ones, y = fives

x + y = 19 ... x = 19 - y

x + 5y = 59

19 - y + 5y = 59

19 + 4y = 59

4y = 59 - 19

4y = 40

y = 40/4

y = 10 < = = = there are 10 five dollar bills

x + y = 19

x + 10 = 19

x = 19 - 10

x = 9 < = = = there are 9 one dollar bills