
Economics is not math. There is no important concept in this course that cannot be explained without mathematics. That said, math is a tool that can be used to illustrate economic concepts. Remember the saying a picture is worth a thousand words? Instead of a picture, think of a graph. It is the same thing. Economists use models as the primary tool to derive insights about economic issues and problems. Math is one way of working with (or manipulating) economic models.

A graph is a a visual representation of numerical information. It is a diagram - a series of one or more points, lines, line segments, curves, or areas - that represents the variation of a variable (price) in comparison with that of one or more other variables (quantity), Graphs condense detailed numerical information to make it easier to see patterns and trends among data.
What this 36-second video to help you make sense of the graphh above.