How much does each kind of dish cost?

Question

I bought 3 appetizers and 2 meals at a restaurant and spend $14. I went back another day and got 4 appetizers in one meal for $12

Answer 1

3a +2m = 14

4a + m = 12

8a +2m =24

subtract

3a +2m = 14

to get

5a = 10

appetizer costs $2 each

m = 12-4(2) = $4 for one meal

Answer 2

3a + 2m = 14

4a + 1m = 12

Hint: multiply bottom by -2 and add to top.