A high school student plans to buy two types of binders to organize her study materials for her classes, 1-inch binders and 2-inch binders. She purchases 4 one-inch binders and 3 two-inch binders for a total before sales tax of $12. Her brother decides that being organized is a good idea and purchases 2 one-inch binders and 5 two-inch binders for a total before sales tax of $13. How much does a two-inch binder cost before sales tax?