This document discusses labeling variables in functions. It provides examples of word problems and their corresponding functions with labeled variables. The first problem is about a person buying comics for $2 each from an initial $187. The function is f(x)=187-2x, where x is the number of comics bought and f(x) is the amount of money left. The second problem is about collecting canned goods, with an initial 91 cans and collecting 10 cans per week. The function is f(x)=10x+91, where x is the number of weeks and f(x) is the number of cans collected. The document emphasizes the importance of labeling both variables in a function.