The relationship shown by the data in the table is not linear because the slope is not constant.
A linear function is a function that has a positive relationship between its variables.
Therefore, an increase in one variable (input variable) causes an increase in the other variable (output variable) because the variables are directly proportional.
Mathematically, the graph of a linear function is a straight-line and its slope is always constant.
Now , we would find the slope of the data:
[tex]Slope = \frac{40 - 25}{2 - 1}\\\\Slope = \frac{15}{1}[/tex]
Slope = 15
[tex]Slope = \frac{60 - 40}{3 - 2}\\\\Slope = \frac{20}{1}[/tex]
Slope = 20
Since the slope is not constant, the relationship shown by the data in the table is not linear.
