A proportional relationship is formally associated with an equation, and the slope of the line representing the proportional relationship is associated with the notion of unit rate.
What to look forThis lesson focuses on the fact that a proportional relationship can be described by an equation of the form y = kx, where k is a positive constant, often called a constant of proportionality. The rate of change in y for a given unit in x will be constant for the points on the line.
Order the equations below in terms of steepest slope to least steep.
a. y = x
b. y = 2x
c. y = x
d. y = x
Answer: b, d, a, c