Question

What is direct variation?

Answer 1

A direct variation is when two variable quantities have a constant (unchanged) ratio.
It is said that one variable "varies directly" as the other.

Answer 2

In the direct variation ' y varies directly as x ," means that when x increases, y increases by the same factor. In other words, y and x always have the same ratio: y/x= k
We can also express the relationship between x and y as: y = kx
where k is the constant of variation.