Write a system of equations to describe the situation below, solve using any method, and fill in the blanks. Cora and her friend Anna are each baking apple pies and tarts for a bake sale, using the same recipes. Cora baked 10 apple pies and 6 apple tarts, using a total of 100 apples. Anna made 7 apple pies and 8 apple tarts, which used 89 apples. How many apples does each dessert require?
An apple pie uses ___ apples and an apple tart requires ___apples.