We must identify if we can use a linear equation
For the first table we must calculate the slopes of the lines for two pair of points
First pair of points ( 28, 7) and (12,3)
Second pair of points ( 4, 1) and (32,8)
We can deduce, the slopes are the same, so, they belong to the same equation wich can be Y = 1/4 * X. Other equation could be Y= X - 3/4X
For the second table we notice that the input values are the same as output values, so the equation could be Y=X. other equation could be Y= 2X - X
For the third table we notice that if we add 2 units to each input value we get the output values. So the equation could be Y= X + 2. Other equation could be Y = (2X + 4)/2