A proportional relationship between two quantities is a relationship in which the ratio of one quantity to the other quantity is equivalent.
Proportional Relationships in Equations
A proportional relationship can be written as an equation in the form “y=kx” where the “k” represents a rate.
Proportional Relationships in Graphs
The graph of a proportional relationship is always a straight line (linear) that goes through the origin
Proportional Relationships in Tables
A table represents a proportional relationship when there is a constant rate of change and when the input (x) equals zero and the output (y) equals zero.
Proportional vs Non-proportional
Proportional relationships are always linear however not all linear relationships are proportional. Some linear relationships are non-proportional.