Which table represents linear function?

Answer:
does not represent a linear function.
Step-by-step explanation:
For the function to be linear, the slope must be the same for every poknt along the function. If is not, then is not a linear function.
Let us now calculate the slope;
[tex]m = \frac{y2 - y1}{x2 - x1} [/tex]
We shall take the first two points
[tex]m = \frac{4 - 2}{2 - 1} \\ m = \frac{2}{1} \\ m = 2[/tex]
Next we shall take the 2nd and 3rd points
[tex]m = \frac{8 - 4}{3 - 2} \\ m = \frac{4}{1} \\ m = 4[/tex]
The slope is not the same for these two different point, hence this table does not represent a linear function.