Key Concepts • The constant of proportionality is the _ value of the ratio between two proportional quantities.

• To find the constant of proportionality on a graph, find the y-value when the x-value is
_ .

• You can use _ reasoning to find the constant of proportionality when the x-value of 1 is not labeled on a graph.

• A proportional relationship is sometimes described by words. Setting up a table to find the _ of proportionality can be useful.