2.4 Graphing Economic Theories LO 5
A functional relation can be expressed in words, in a table giving
specific values, in a mathematical equation, or in a graph.
A graph of two variables has a positive slope when they both increase
or decrease together and a negative slope when they move in
opposite directions.
The marginal response of a variable gives the amount it changes in
response to a change in a second variable. When the variable is
measured on the vertical axis of a diagram, its marginal response at a
specific point on the curve is measured by the slope of the line at that
point.
Some functions have a maximum or minimum point. At such points,
the marginal response is zero.