A bakery uses a certain amount of flour for cakes and cookies. Each cake requires 3.5 cups of flour, and each cookie requires 0.5 cups of flour. The total amount of flour used is represented by the equation $3.5C+0.5K=42$, where $C$ is the number of cakes and $K$ is the number of cookies. If the bakery makes 6 cakes, how many cookies can be made with the remaining flour?