Final answer:
Economists use models to analyze economic behavior and predict outcomes. Models are constructed by using theories and expressing them as diagrams, graphs, or equations.
Step-by-step explanation:
Economists construct models by using theories and expressing them as diagrams, graphs, or even mathematical equations. They do not figure out the answer first and then draw the graph; instead, they use the graph of the theory to help them figure out the answer. Models are used to analyze economic behavior, predict outcomes, and understand concepts like supply and demand.