Is x=-7 a direct variation and if so what is the constant?

1 Answer
Jun 1, 2015

x=-7 is not a direct variation.

It is not a variation of any kind. x is a constant.

A necessary (but not sufficient) condition for an equation to be a direct variation is that the equation have two variables.

Even then the equation would not be a direct variation unless it could be expressed in the form
color(white)("XXXXX")y=c*x for some constant c
(of course the letters y and x could be replaced by any other two symbols as the variables).