Muffin and Cupcake Sales Problem

A bakery sells muffins and cupcakes. Each muffin costs $2, and each cupcake costs $3. One day, the bakery sold a total of 20 items consisting of muffins and cupcakes. The total revenue from these sales was $42.

Let the number of muffins sold be represented by the variable m and the number of cupcakes sold by the variable c. You can set up a system of equations based on the information above:

1. m + c = 20

2. 2m + 3c = 42

To find the number of muffins sold, solve the system of equations.