Which table represents a linear function?

Which table represents a linear function?

Ans. Table 2 represents a linear function.

A function is linear if it increases at a steady rate. That is, for every equal change in the input variable (x), the output variable (f(x)) increases by the same, constant value. We can verify this by finding the slope between each consecutive pair of points.

For Table 2, every time x is raised by 1 (0 to 1, 1 to 2, etc.), the value of f(x) always rises by 6 (4 to 10, 10 to 16, etc.). This is the constant change, or slope, and it informs us that Table 2 is linear. For Table 1, however, we can see that every time that x is raised by 1, the value of f(x) doubles, so it is not linear, but exponential.