system of equations

Question

At McDOvers- I bought 2 value meals and 3 sandwiches for a total bill of $12.55 on Monday. Friday, I went back and bought 4 value meals and only 1 sandwhivh for a bill of $ 15.15. What is the cost of a value Meal? How much for a sandwich?

Answer 1

2v + 3s = 12.55

4v + s = 15.15

4v + 6s = 25.10

subtract 2nd from last equation to get

5s = 9.95

s = 9.95/5 = $1.99 for a sandwich

v= (15.15-1.99)/4 = 13.16/4 = $3.29 for a value meal

2(329)+3(199)=658+597= 1255