Is #c = 3v# a direct variation, inverse variation, or neither?

1 Answer
Jun 11, 2015

#c = 3v# is a direct variation.

Explanation:

In a direct variation, one number changes based on how the other changes. Basically, some number #x# will always be a certain number #k# times more than its partner #y#. This is usually written as:

#y = kx#

In an inverse variation, two numbers change so that their product will stay constant. Unlike a direct variation, one number gets bigger while the other gets smaller. This is usually written as:

#yx = k#

Now look at the original equation: #c = 3v#
We can see that #v# will always change relative to #c#, by a factor of 3.
This is also an equation of the form #y = kx# where #k# is a constant.
So, this is a direct variation.