Students should use their prior knowledge from seventh grade concerning the constant of proportionality to understand the relationship between proportional situations in a variety of forms. A proportional relationship can be represented by the equation y = kx where k is the constant rate of change, unit rate, or slope.

The cost of bananas per pound is represented in the table below.

 

 

Write an equation that represents the cost of buying x amount of bananas. Justify your thinking.

 

8.5 Proportionality. The student applies mathematical process standards to use proportional and non-proportional relationships to develop foundational concepts of functions. The student is expected to:

(A) represent linear proportional situations with tables, graphs, and equations in the form of y = kx