Let D = cost of a drink abd B = the cost of a bag of popcorn
Arianna:10D + 5B = 118.75
Samantha: 9D + 10B = 157.75
No matter which way you solve this set, it will be messy!
Multiply the first equation by 2 and subtract the 2nd equation
11D=79.75
D=7.75
Use either of the equations and the value to D to obtain the value of B