# Proportionality - Functions

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(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;

(B)  represent linear non-proportional situations with tables, graphs, and equations in the form of y = mx + b, where b ≠ 0;

(C)  contrast bivariate sets of data that suggest a linear relationship with bivariate sets of data that do not suggest a linear relationship from a graphical representation;

(D)  use a trend line that approximates the linear relationship between bivariate sets of data to make predictions;

(E)  solve problems involving direct variation;

(F)  distinguish between proportional and non-proportional situations using tables, graphs, and equations in the form y = kx or y = mx + b, where b ≠ 0;

(G)  identify functions using sets of ordered pairs, tables, mappings, and graphs;

(H)  identify examples of proportional and non-proportional functions that arise from mathematical and real-world problems; and

(I)  write an equation in the form y = mx + b to model a linear relationship between two quantities using verbal, numerical, tabular, and graphical representations.