Question

Is the relationship between the variables in the table a direct variation, an inverse variation, or neither? If it is a direct or inverse variation, write a function to model it.
A.
direct variation; y = 12x

B.
inverse variation; y = 432/x

C.
neither

Answer 1

The given choices for the model to fit the data are
y = 12x
y = 432/x

To determine whether any of the models fits the data, construct the table shown below.

  x       Data    y=12x   y=432/x
----  ----------  ----------  -------------
-6       -72         -72         -72 
-4       -48         -48       -108
-3       -36         -36       -144
  1         12           12        432

It is clear that the model y = 12x  fits the data perfectly while the inverse function does not.

Answer: A. Direct variation, y = 12x