Answer:
<h2>B) Δy</h2>
Step-by-step explanation:
Where we analyse a linear function, we must consider variations of each variable.
Also, linear functions variate according to its constant ratio of change, which is defined as
Which is the variation of the vertical value, regarding x-values.
So, if we want to show this variation, we must include a colum , which shows the variation we need, because it's the dependent value, then we can analyse the variation of the function for a certain x-interval.
Therefore, the right answer is B.