The given equation is a combined variation.
We have been given an equation is

This is an equation in which we have three variables and one constant.
This can not be the case of direct or inverse variation because in direct or inverse variation we have only two variables. Whereas, here we have three variables.
So, Direct and inverse options are discarded.
So, either It can be joint or combined
In joint variation both the variables are directly proportional
Hence, given equation is not joint because if we rewrite the equation we will get
both the variables are not directly proportional.
In combined, one variable is directly proportional and the other one is inversely proportional.
From
we can see that z is directly proportional and x is inversely proportional.
Hence the answer is, the given equation is combined variation.
To learn more about variations click here brainly.com/question/2375770
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