Imagine telling a friend about your favorite coffee and donut shop. Your friend asks how much it charges for a cup of coffee and a doughnut. While you can't remember how much each one costs individually, you do remember that's the last time you ordered one coffee and two donuts, your bill was $7.00. And today, when you bought two coffees and three Donuts, your bill came to $12.00.

Write a system of linear equations to represent the above situation.