To determine which of the given equations is a linear function, we can evaluate each one:
-
: This is in the form , where and . This is a linear function. -
: This equation involves , which means it's not linear (it is a rational function). -
: This involves , which indicates it is a cubic function, not linear. -
: We can rearrange this into the form : This is also a linear function. -
: This involves , which indicates it is a quadratic function, not linear.
Thus, the options that represent linear functions are:
(which can be rearranged to a linear form)
Final Response: Both