Direct variation occurs when a variable varies directly with another variable. That is, as the x-variable increases, the y-variable also increases.
The ratio of between y-variable and x-variable would be constant.
Direct variation can be represented by the equation, , where k is a constant. Thus,
From the table given, it seems, as x increases, y also increases. Let's find out if there is a constant of proportionality (k).
Thus, ratio of y to x,
k = 0.5.
If the given table of values has a direct variation relationship, then, plugging in the values of any (x, y), into , should give us the same constant if proportionality.
Let's check:
When x = 2, and y = 1:
,
,
When x = 3, y = 1.5:
,
When x = 5, y = 2.50:
,
The constant of proportionality is the same. Therefore, the relationship forms a direct variation.